ArticlePDF Available

Effects of Persea americana leaf extracts on body weight and liver lipids in rats fed hyperlipidaemic diet

Authors:
  • The National Institute for Medical Research, Yaba

Abstract and Figures

The effects of aqueous and methanolic leaf extracts of Persea americanaon body weight and liver lipids in rats were studied. Male albino rats were fed a modified diet containing 0.5% cholesterol and 0.25% cholic acid to provoke hyperlipidaemia. The hyperlipidaemic rats were given 10 mg/kg body weight of either aqueous or methanolic extract of P. americana leaf daily for 8 weeks. There were no significant differences (p>0.05) in the overall body weight gain of the hyperlipidaemic rats compared to normal control. However, the administration of the aqueous and methanolic extracts provoked 14 and 25% reduction, respectively, in the body weight gain of the treated rats compared to the hyperlipidaemic control. Mean liver weights were markedly increased (p<0.05) in rats fed hyperlipidaemic diet (groups B, C and D: 70, 69 and 57%, respectively) compared to normal control rats. The methanolic extract provoked a minimal (8%) decrease in mean liver weight compared to the hyperlipidaemic control rats. It can be hypothesized that P. americana leaf extracts increase catabolism of lipids accumulated in adipose tissue causing a decrease in body weight but does not influence liver lipid levels in rats.
Content may be subject to copyright.
African Journal of Biotechnology Vol. 6 (8), pp. 1007-1011, 16 April 2007
Available online at http://www.academicjournals.org/AJB
ISSN 1684–5315 © 2007 Academic Journals
Full Length Research Paper
Effects of Persea americana leaf extracts on body
weight and liver lipids in rats fed hyperlipidaemic diet
B. I. C. Brai1, 2 *, A. A. Odetola2 and P. U. Agomo1
1Nigerian Institute of Medical Research, P. M. B. 2013, Yaba. Lagos, Nigeria.
2Department of Biochemistry, University of Ibadan, Ibadan, Nigeria.
Accepted 31 August, 2006
The effects of aqueous and methanolic leaf extracts of Persea americana on body weight and liver
lipids in rats were studied. Male albino rats were fed a modified diet containing 0.5% cholesterol and
0.25% cholic acid to provoke hyperlipidaemia. The hyperlipidaemic rats were given 10 mg/kg body
weight of either aqueous or methanolic extract of P. americana leaf daily for 8 weeks. There were no
significant differences (p>0.05) in the overall body weight gain of the hyperlipidaemic rats compared to
normal control. However, the administration of the aqueous and methanolic extracts provoked 14 and
25% reduction, respectively, in the body weight gain of the treated rats compared to the
hyperlipidaemic control. Mean liver weights were markedly increased (p<0.05) in rats fed
hyperlipidaemic diet (groups B, C and D: 70, 69 and 57%, respectively) compared to normal control rats.
The methanolic extract provoked a minimal (8%) decrease in mean liver weight compared to the
hyperlipidaemic control rats. It can be hypothesized that P. americana leaf extracts increase catabolism
of lipids accumulated in adipose tissue causing a decrease in body weight but does not influence liver
lipid levels in rats.
Key words: Persea Americana, body weight gain, hyperlipidaemia, leaf extracts, albino rats.
INTRODUCTION
Lifestyle changes accompanying industrialization have a
significant impact on the health of the people. The
modernization of societies appears to result in a dietary
pattern that is high in saturated fats and refined sugars
and is low in fibre content. Analyses of available
aggregate data sources indicate that a shift towards
“western diets” high in saturated fat and sugar and low in
fibre is occurring (Reddy and Yusuf, 1998; Popkin, 2002).
In Nigeria, there appears to be a cultural transition
towards a more westernized lifestyle. The traditional
foods consisting mainly of roots, cereals, beans, tubers
and vegetables are giving way to fatty foods, sweet
snacks and drinks which have too much calories. These
changes in dietary pattern among Nigerians, coupled with
*Corresponding authors E-mail: barthrem@yahoo.com. Tel:
234-803 333 9286. Fax: 234-1-342 5171.
changes in physical activity patterns, increased use of
tobacco products and alcohol are possible causes of
hyperlipidaemia and obesity which are becoming
important factors in the pathogenesis of chronic
degenerative diseases such as cardiovascular disease,
diabetes and cancer.
It has been postulated that in many individuals excess
weight gives rise to cardiovascular disease, type 2
diabetes mellitus, hypertension, stroke, dyslipidaemia,
osteoarthritis, and some cancers (Eckel et al., 2006;
Burton et al., 1985; Ezzati et al., 2005). It is also known
that fatty liver disease is associated with hyperlipidaemia
and obesity (Sharadi and Eldad, 2000). Plants were the
major source of materials which the ancient man resorted
to for combating various ailments and thus preserving his
health (Akah and Ekekwe, 1995). At present, a number of
botanicals are still being used in folk-medicine for
treatment of different diseases.
Persea americana (avocado or alligator pear) is an
almost evergreen tree belonging to the laurel family,
1008 Afr. J. Biotechnol.
Table 1. Mean weekly body weights of rats fed with extracts of P. americana.
Week A B C D
0 65.95 ± 3.46 65.88 ± 11.23 93.13 ± 9.62 87.37 ± 11.01
1 69.52 ± 7.80a 77.95 ± 13.89b 101.99 ± 12.30 b 95.64 ± 9.18 b
2 81.45 ± 6.93 85.12 ± 14.61 114.16 ± 14.24 108.10 ± 10.40
3 90.13 ± 8.64a 94.20 ± 17.34a 117.62 ± 15.12b 111.41 ± 10.4b
4 107.58 ± 9.59 a 97.19 ± 15.52b 124.20 ± 16.19b 112.89 ± 25.82 b
5 123.82 ± 9.46 115.24 ± 17.21 134.92 ± 19.99 124.45 ± 27.44
6 135.83 ± 6.84 125.27 ± 19.60 152.86 ± 24.72 141.53 ± 29.88
7 141.31 ± 7.37 135.60 ± 16.54 160.18 ± 24.65 150.55 ± 30.11
8 154.13 ± 9.50 a 152.59 ± 20.80 a 167.56 ± 25.74 b 152.35 ± 29.93 b
Values are expressed as means ± SD for six rats.
Values not sharing a common superscript letter differ significantly at p<0.05.
Group A, rats fed standard chow; Group B, rats fed modified diet; Group C, rats fed modified diet + 10 mg/kg body weight of
aqueous extract of P.americana; Group D, rats fed modified diet + 10 mg/kg body weight methanolic extract of P. americana.
Lauraceae. It is indigenous to Central and South America
but is now cultivated in the United States, Asia, parts of
Europe and tropical Africa. The leaves are alternate, dark
green and glossy on the upper surface, whitish on the
underside; variable in shape (lanceolate, elliptic, oval,
ovate or obovate) 7.5 40 cm long (Morton, 1987).
According to Morton (1987), avocado has many
medicinal uses. The leaves are chewed as a remedy for
pyorrhea. The aqueous extract of the leaves has a
prolonged antihypertensive effect. The leaf decoction is
taken as a remedy for diarrhea, sore throat and
haemorrhage. It allegedly stimulates and regulates
menstruation. Recently, the aqueous leaf extract of P.
Americana was reported to possess hypoglycemic
activity (Antia et al., 2005). The purpose of this study was
to test whether the leaf extract of P. americana would
influence body weight gain and liver lipid levels in a rat
model.
MATERIALS AND METHODS
Preparation of plant extracts
Fresh leaves of P. americana were obtained from a cultivated plant
in Lagos. The leaves were air-dried and pulverized in a Waring
blender and the aqueous and methanolic extracts prepared by
means of Soxhlet extraction. The extracts were evaporated to
dryness in an oven at 40°C and stored in clean sterile vials until
required.
Animal feeding
Albino rats were divided into four feeding groups (A, B, C and D) of
six rats per group. Group A was fed standard rat chow and water.
Groups B to D were fed a modified diet containing 20% groundnut
oil, 0.5% cholesterol and 0.25% cholic acid to provoke
hyperlipidaemia. In addition, groups C and D rats were orally
treated with aqueous and methanolic extracts of P. americana
respectively at a daily dose of 10 mg/kg body weight. Rats in group
B acted as hyperlipidaemic control and received water orally. The
animals were observed daily and weighed weekly for 2 months.
At the end of the feeding period, the animals were sacrificed under
pentobarbital anaesthesia (100 mg/kg body weight). The livers,
hearts, brains, kidneys and lungs were quickly excised and
perfused with chilled 1.15% (w/v) KCl solution in order to remove all
traces of contaminating haemoglobin. The tissues were blotted dry,
weighed and stored at 80oC pending analysis.
Determination of liver lipids
Liver lipids were extracted according to the method of Folch et al.
(1957). Liver total cholesterol (T-CHOL), high-density lipoproteins
(HDL-CHOL), low-density lipoproteins (LDL-CHOL), and
triacylglycerols (TAG) were measured using appropriate kits
supplied by RANDOX Laboratories Ltd., Crumlin, United Kingdom.
Statistical analysis
Data, expressed as mean ± S.D, were analyzed by analysis of
variance (ANOVA). Statistical significance of the difference of the
means was evaluated by Student’s t-test. Differences were
considered statistically significant if the p value was < 0.05.
RESULTS
Table 1 shows the mean weekly body weights of rats in
the four experimental groups. In the first week, body
weight increase was significantly higher (p<0.05) in the
hyperlipidaemic rats compared to normal control. Also,
there were significant differences (p<0.05) in body weight
increase in the 3rd, 4th and 8th weeks among the various
groups. Body weight increase in the second week was
least in hyperlipidaemic control rats. However, in the 3rd
and 8th weeks body weight increase was significantly
lower (p<0.05) in the treated groups compared to the
normal and hyperlipidaemic control rats.
However, there were no significant differences (p>0.05)
in the overall body weight gain and the overall weight
Brai et al. 1009
0
10
20
30
40
50
60
70
80
90
100
A B C D
Weight Gain (g)
Figure 1. Mean overall body weight gain in rats fed with extracts of P. americana. Values are
means ± SD (n = 6). Group A =fed standard rat chow; Group B =fed modified diet; Group C =fed
modified diet + 10 mg/kg body weight aqueous extract of P. americana; Group D = fed modified
diet + 10 mg/kg body weight of methanolic extract of P. americana.
0
1
2
3
4
5
6
7
8
A B C D
Liver Weight (g)
Figure 2. Mean liver weights in rats fed with extracts of P. americana. Values are means ± SD (n = 6).
Group A =fed standard rat chow; Group B =fed modified diet; Group C =fed modified diet + 10 mg/kg
body weight aqueous extract of P. americana; Group D = fed modified diet + 10 mg/kg body weight of
methanolic extract of P.americana.
gain per cent for groups A, B, C and D were 133.71,
131.62, 79.92 and 74.37, respectively. However rats
treated with both aqueous and methanolic P. americana
leaf extracts showed decrease in overall body weight
gain (14 and 25%, respectively) compared to the
hyperlipidaemic control (Figure 1).
Figure 2 shows the mean liver weights of rats in all the
groups. Liver weight was markedly increased (p<0.05) in
1010 Afr. J. Biotechnol.
Table 2. Mean weight of organs of rats fed with extracts of P. americana.
Organ A B C D
Kidney 0.93 ± 0.13 0.88 ± 0.09 0.83 ± 0.10 0.80 ± 0.14
Lungs 0.702 ± 0.07 0.72 ± 0.12 0.87 ± 0.11 0.90 ± 0.22
Heart 0.53 ± 0.14 0.53 ± 0.07 0.55 ± 0.07 0.55 ± 0.12
Brain 1.40 ± 0.12 1.42 ± 0.12 1.60 ± 0.08 1.57 ± 0.04
Values are expressed as means ± SD for six rats.
Group A, rats fed standard chow; Group B, rats fed modified diet; Group C, rats fed modified diet + 10 mg/kg body weight of
aqueous extract of P. americana; Group D, rats fed modified diet + 10 mg/kg body weight methanolic extract of P.
americana.
Table 3. Liver lipid profile (mg/dl) of rats fed with extracts of P. americana.
Lipid A B C D
T-CHOL 47.53 ± 8.56a 599.53 ± 97.97b 616.43 ± 56.81b 610.30 ± 39.47b
LDL-CHOL 35.15 ± 11.01a 415.36 ± 136.62b 415.54 ± 48.76b 416.28 ± 8.10b
HDL-CHOL 5.11 ± 2.11a 11.67 ± 3.73b 9.68 ± 5.71b
12.41 ± 3.93b
TAG 36.73 ± 10.05a 862.50 ± 207.43b 956.03 ± 280.68b 908.02 ± 192.48b
Values are expressed as means ± SD for six rats.
Values not sharing a common superscript letter differ significantly at p<0.05
Group A, rats fed standard chow; Group B, rats fed modified diet; Group C, rats fed modified diet + 10 mg/kg body weight of
aqueous extract of P.americana; Group D, rats fed modified diet + 10 mg/kg body weight methanolic extract of P.americana
rats fed the hyperlipidaemic diet (groups B, C and D: 70,
69 and 57%, respectively) compared to normal control
rats. Other organs did not show any significant difference
(p>0.05) in weight although brain weight was higher in
rats treated with P. americana leaf extracts compared to
normal and hyperlipidaemic control (Table 2). The liver
lipid profile of the rats in the four experimental groups is
shown in Table 3. Liver T-CHOL, LDL-CHOL and TAG
were significantly raised (p<0.05) in rats fed
hyperlipidaemic diet compared to normal control.
DISCUSSION
Throughout the period of experiment there was no
significant difference in food consumption in all groups
(data not shown). The body weights of rats in each group
were determined weekly as a general index of overall
health. Based on body weight, each group of rats
tolerated the treatment diet when compared with rats fed
standard chow. It is evident from our study that the
administration of aqueous and methanolic leaf extracts of
P. americana provoked a reduction in body weight gain
compared to the hyperlipidaemic control. It could be that
P. americana leaf extracts increase the catabolism of
lipids accumulated in adipose tissue resulting in a
decrease in mean body weight.
Liver weights were significantly increased by the intake
of hyperlipidaemic diet as compared to normal control
rats, and it was accompanied by significant increase in
liver cholesterol level. This result is in agreement with
previous report that liver weights were significantly
enhanced by intake of hyperlipidaemic diet containing 1%
cholesterol, 0.5% cholic acid and 25% coconut oil (Zulet
et al., 1999). It was observed that the excised livers of
rats fed hyperlipidaemic diet were golden yellow in
colour. This is similar to the findings that treatment with
poloxamer-407 to induce hypercholesterolemia result in
the development of golden yellow livers in C57BL/6 mice
(Palmer et al., 1998; Johnston et al., 1999).
There was a 13-fold increase in hepatic cholesterol
concentrations in the hyperlpidaemic rats compared to
control. A 2-fold increase in hepatic cholesterol had
previously been reported in rats relative to control when
both were fed a high-fat atherogenic diet containing
cholic acid (Shefer et al., 1992). Also, feeding diets
supplemented with cholesterol and cholic acid markedly
increased liver weights (two-fold), hepatic triglycerides
(3.7 fold) and cholesterol (12 fold) concentrations in
geese (Eder, 1999). Inclusion of saturated fatty acids in
the diet has been shown to produce
hypercholesterolemic effect in rats (Lutz et al., 1994;
Zulet et al., 1999). The groundnut oil included in the
hyperlipidaemic diet in this study contained 17%
saturated fatty acids and this could account for the
difference in increase in the accumulation of cholesterol
in the liver in this study. It is possible that the normal
catabolism of liver lipids was impaired in the rats fed
hyperlipidaemic diet with consequent accumulation of
lipids in the liver. The hepatic cholesterol concentrations
in the treated rats and the hyperlipidaemic control were
similar suggesting that both aqueous and methanolic leaf
extracts of P. americana at a concentration of 10 mg/kg
body weight used in this study could not exert
antihyperlipidaemic effect in the liver.
In conclusion, it can be hypothesized that P. americana
leaf extract increases catabolism of lipids accumulated in
adipose tissue causing a decrease in mean body weight
gain. However, it might be necessary to determine
whether higher concentrations of P. americana leaf
extract would reduce liver lipid levels in obesity and fatty
liver conditions.
REFERENCES
Akah PA, Ekekwe RK (1995). Ethnopharmacology of some Asteraceae
family used in Nigerian traditional medicine. Fitoterapia 66:351-356.
Antia BS, Okokon JE, Okon PA (2005). Hypoglycemic activity of
aqueous leaf extract of Persea americana Mill. Indian J. Pharmacol.
37: 325-326.
Burton BT, Foster WR, Hirsch J, Vanltallie TB (1985). Health
implications of obesity: NIH consensus development conference. Int.
J. Obes. Relat. Metab. Disord. 9: 155-169.
Eckel RH, Kahn R, Robertson RM, Rizza RA (2006). Preventing
cardiovascular disease and diabetes: A call to action from the
American diabetes Association and American Heart Association.
Diabetes Care 29: 1697-1699.
Eder K (1999). The effect of a combined dietary treatment with
cholesterol and cholic acid on the lipid metabolism of geese at low or
high choline concentrations. Arch. Tierernahr. 52: 285-297.
Ezzati M, Vander Hoorn S, Lawes CMM, Leach R, James WPT, Lopez
AD, Rodgers A, Murray CJL (2005). Rethinking the “diseases of
affluence” paradigm: Global patterns of nutritional risks in relation to
economic development. PLoS Med. e133 doi:10.1371
/journal.pmed.0020133.
Folch J, Lees M, Sloane–Stanley GH (1957). A simple method for the
isolation and purification of total lipids from animal tissues. J. Biol.
Chem. 226: 497–590.
Johnston TP, Baker JC, Jamal AS, Hall D, Emeson EE, Palmer WK
(1999). Potential down regulation of HMG-CoA reductase after
Brai et al. 1011
prolonged administration of P-407 in C57BL/6 mice. J. Cardiovasc.
Pharmacol. 34: 831-842.
Lutz M, Cortez J, Vinet R (1994). Dietary fats and cholesterol
supplementation effects on aortic and lipid response in rats. J. Nutr.
Biochem. 5:446-450.
Morton J (1987). Avocado. In: Fruits of warm climates.ed. Julia F.
Morton, Miami FL. 91–102.
Palmer WK, Emeson EE, Johnston TP (1998). Poloxamer 407-induced
atherogenesis in the C57BL/6 mouse. Atherosclerosis 136:115-123.
Popkin BM (2002). An overview on the nutrition transition and its health
implications: The Bellagio Meeting. Public Health Nutr. 5:93–103.
Reddy KS, Yusuf S (1998). Emerging epidemic of cardiovascular
disease in developing countries. Circulation 97:596–601.
Sharadi Y Eldad A (2000). Non-alcoholic fatty liver disease is
associated with hyperlipidaemia and obesity. Am. J. Med. 109: 171
Shefer S, Nguyen LB, Salen G, Ness GC, Chowdhary IR, Lerners S,
Batta AK, Tint GS (1992). Differing effects of cholesterol and
taurocholate on steady state HMG-CoA reductase and cholesterol
7-hydroxylase activities and mRNA levels in the rat. J. Lipid Res.
33:1193–1200.
Zulet MA, Barber A, Garcin H, Higueret P, Martinez JA (1999).
Alteration in carbohydrate and lipid metabolism induced by a diet rich
in coconut oil and cholesterol in a rat model. J. Am. Coll. Nutr. 18:36–
42.
... Statistics are showing a continuing shift towards "Western Diets". 1,2 Obesity is an emerging problem which results not only in significant comorbid conditions but also in death of people because of the disease which are related to weight in addition to abridged life quality. Obesity and accumulation of fats around visceral organs of body prompts the complications such as atherosclerosis, hepatic steatosis, and type2 diabetes. ...
... 8 On the other hand another study conducted in patients who were taking statins for one year showed an increase in body weight. 9 Purpose of Study/Objectives: (1) To determine effects of high doses of atorvastatin on body weight, liver weight and liver/body weight ratio in albino rabbits. (2) To compare the effect of three increasing doses of ethanolic extract of Raphanus sativus leaf with high doses of atorvastatin on body weight, liver weight and liver/body weight ratio in albino rabbits. ...
Negative Results
Full-text available
Background: Obesity is a global health problem. The chances of metabolic disorders such as type 2 diabetes, systemic hypertension, cardiovascular disease, dyslipidemia, and atherosclerosis are increased due to obesity. Objective: (1) To determine effects of high doses of atorvastatin on body weight, liver weight and liver/body weight ratio in albino rabbits. (2) To compare the effect of three increasing doses of ethanolic extract of Raphanus sativus leaf with high doses of atorvastatin on body weight, liver weight and liver/body weight ratio in albino rabbits. Study Design: Experimental study. Settings: Department of Physiology and Pharmacology, University of Agriculture, Faisalabad Pakistan. Duration: 1 year. Methodology: The ethanolic extract of Raphanus sativus was screened for additional beneficial effects on body weight and liver weight by atorvastatin. Results: The results were compared with normal and experimental control by measuring body weight and liver weight after 28 days. There was a very highly significant reduction in weight in all groups when compared with the negative control group A. when compared to the positive control group B no significant change was observed in group C, D and E. The liver weight decreased when Raphanus sativus was added to atorvastatin and a significant effect was seen in in group E. Conclusion: Atorvastatin in high doses decreased the body weight but the combined use of Raphanus sativus and atorvastatin had no significant effect regarding liver weight addition of Raphanus sativus showed a decrease in weight of liver while an increase was seen with atorvastatin alone.
... Statistics are showing a continuing shift towards "Western Diets". 1,2 Obesity is an emerging problem which results not only in significant comorbid conditions but also in death of people because of the disease which are related to weight in addition to abridged life quality. Obesity and accumulation of fats around visceral organs of body prompts the complications such as atherosclerosis, hepatic steatosis, and type2 diabetes. ...
... 8 On the other hand another study conducted in patients who were taking statins for one year showed an increase in body weight. 9 Purpose of Study/Objectives: (1) To determine effects of high doses of atorvastatin on body weight, liver weight and liver/body weight ratio in albino rabbits. (2) To compare the effect of three increasing doses of ethanolic extract of Raphanus sativus leaf with high doses of atorvastatin on body weight, liver weight and liver/body weight ratio in albino rabbits. ...
Article
Full-text available
Objectives: To investigate hepato-protective effect of ethanolic leave extract of Raphanus sativus against atorvastatin induced hepatotoxicity in albino rabbits. This study conducted at department of Physiology and Pharmacology, University of Agriculture, Faisalabad. The ethanolic extract of Raphanus sativus was prepared for hepatoprotective effect against hepatotoxicity produced by atorvastatin. Results: The results were compared with normal and experimental control. Serum was tested for ALT, AST, Alkaline Phosphatase and Bilirubin along with histological studies. Ethanolic extract of Raphanus sativus with 100mg/kg. of body weight dosage developed some changes representing hepatotoxicity but higher doses showed an increase in toxicity as observed on histologic sections. A reduction in fibrosis and cholestasis was observed which needs further evaluation.Ethanolic extract of raphanus sativus did not show any amelioration in the increased enzymes level however a reduction in cholestasis was observed as represented by decreases in alkaline phosphatase levels also confirmed by histological studies.
... Also, this study has shown that the treatment of rabbits with tramadol caused significant increases the catabolism of lipids in the adipose tissue, resulting in significant reduction in body weight of rabbits at a later stage during the treatment period. Similar results were reported by [16] in Persea americana leaf extracts treated rats. Opiate use is known to decrease the levels of sex hormones in both sexes and this is thought to be responsible for the diminished fertility of both male and female opiate users [17]. ...
Article
Full-text available
Tramadol manhandle straightforwardly impacts the discharge of luteinizing hormone and follicular stimulating g hormone from the front pituitary organ that diminishes the common discharge of luteinizing hormone in a pulsatile way, resulting in a negative impact on male testiclesdue to lower levels of testosterone hormone. Animals were orally given 40 mg/kg B.W. doses of tramadol. The tried measurements were given to rabbits each other day for 6 weeks. Tramadol significantly decreased body weight (BW), weight of brain, testes, testosterone, estradiol, follicle stimulating hormone (FSH), luteinizing hormone (LH), triiodothyronine (T3) and thyroxin hormone (T4). While, it caused significant increase in thiobarbituric acid-reactive substances (TBARS) concentrations in plasma, testes and brain. Keywords: Tramadol; Hormone; TBARS; Rabbits
... Avocados are a rich source of nutrients and phytochemicals. Some scientific records on the pharmacological activities of the avocado pear include its vasorelaxant activity (Owolabi et al., 2005), hypotensive activity, analgesic and antiinflammatory activity (Adeyemi et al., 2002), antiviral activity, anticonvulsant effect (Ojewole and Amabeoku, 2006), antiulcer effect (Ukwe and Nwafor, 2004), wound healing activity (Nayak et al., 2008), antihepatotoxic activity, antioxidant activity, hypoglycemic activity (Anita et al., 2005) and effect on body weight (Pliego and Litz, 2007;Brai et al., 2007) . However, there is limited scientific evidence on its effect on hypertension associated biochemical risk factor in high salt induced hypertension in rats. ...
Article
Full-text available
Hypertension is a major health problem throughout the world because of its high prevalence and its association with increased risk of cardiovascular disease. It is usually taken as that level of arterial blood pressure associated with doubling of long-term cardiovascular risk. This study evaluated the anti-hypertensive potential of ethanol extract of Persea americana seed (avocado pear) in male Wistar albino rats. Twenty-four rats were used for this study and they were divided into 6 groups of 4 rats each. Group 1 (normal control), group 2 (hypertensive untreated), group 3 (hypertensive + 10mg/kg b.w of frusemide, a standard anti-hypertensive drug), group 4 through 6 were hypertensive rats administered 200mg/kg, 400mg/kg and 600 mg/kg b. wt of extract. The hypertension was induced by oral administration of 1ml of 18% NaCl for three (3) weeks. The results showed significant (p<0.05) Increase in the VLDL, TAG, Uric acid, Na + concentration in the untreated group compared to the normal control and extract treated group. P. americana aqueous seed extract showed significant (p<0.05) increase in HDL of treated group compared to untreated group. These results validate the forklore use P. americana seed in the management of hypertension.
... With the progress of industrialization, the lifestyle has been changed and has a predominant effect on the health of people. The modernization of societies changes the food habit where people consume more saturated fats and refine sugar instead of foods with high fibre content [6]. ...
Article
Our present study was designed to investigate the comparative anti-obesity efficacy of ethanolic extract of Azadirachta indica A. Juss., Trigonella foenum-graecum L., Allium sativum L. and Zingiber officinale Roscoe in high fat-induced mice with their total phenolic and flavonoid profile. Total phenolic and flavonoid content were determined by Folin–Ciocalteu's and Aluminium chloride UV method respectively. In our study, 55 healthy mice were separated into 11 groups to take their respective treatments. Lipid and uric acid profile were estimated by using the enzymatic colourimetric method. Ethanolic extract of A. indica contained the highest phenolic and flavonoid content. A. indica normal and high fat diet group showed reduced weight gaining tendency than other extract groups. A. indica at a dose of 400 mg/kg body weight significantly (p < 0.001) reduced serum cholesterol (SC), triglyceride (TG), and uric acid (UA) level than other three extracts when compared with the control group. Thus, a considerable correlation was found between serum uric acid reducing potentials of the present experimental extracts with a lipid-lowering profile. Pathological examination revealed that the average weight of liver and kidney were significantly decreased in A. indica normal. Results obtained from the present study it can be concluded that ethanolic extract of A. indica possesses better lipid-lowering efficacy than the other three herbs.
... This suggests that captopril has no effect on the catabolism of lipids in the adipose tissue, resulting in insignificant changes in body weight. Contrary results were reported by 13 in Persea americana leaf extracts treated rats. ...
Article
Full-text available
This study was designed to investigate the effect of captopril on reproductive parameters in male Wistar rats. Ten male Wistar rats (120-140 g) were divided into control (distilled water) and captopril-treated (0.71 mg/kg) groups (5 per group) for hormonal assay, andrological and Histopathological studies. The animals were orally treated on daily basis for 50 days. Plasma testosterone level was assayed using Enzyme-linked Immuno-sorbent Assay (ELISA) and semen analysis was done microscopically. Histology of testes was also done. Data were analyzed using descriptive statistics and student's t-test at p=0.05. Treatment of rats with captopril (0.71 mg/kg) caused no significant (p>0.05) change in testosterone level relative to control. Treatment of rats with captopril (0.71 mg/kg) caused significant (p<0.05) reduction in progressive sperm motility, but induced insignificant (p>0.05) reduction sperm count relative to their respective controls. It can therefore be concluded that captopril probably has deleterious effect on the reproductive function in male rats.
... This suggests that verapamil has no effect on the catabolism of lipids in the adipose tissue, resulting in insignificant changes in body weight. Contrary results were reported by 11 in Persea americana leaf extracts treated rats. ...
Article
Full-text available
This study was designed to investigate the reproductive effect of verapamil on reproductive parameters in male Wistar rats. Ten male Wistar rats (120-140 g) were divided into control (distilled water) and verapamil-treated (1.14 mg/kg) groups (5 per group) for hormonal assay, andrological and Histopathological studies. The animals were orally treated on daily basis for 50 days. Plasma testosterone level was assayed using Enzyme-linked Immuno-sorbent Assay (ELISA) and semen analysis was done microscopically. Histology of testes was also done. Data were analyzed using descriptive statistics and student's t-test at p=0.05. Treatment of rats with verapamil (1.14 mg/kg) caused no significant (p>0.05) change in testosterone level relative to control. Treatment of rats with verapamil (1.14 mg/kg) caused significant (p<0.05) reductions in progressive sperm motility and sperm count relative to their respective controls. It can therefore be concluded that verapamil probably has deleterious effect on the reproductive function in male rats.
Chapter
This chapter describes a number of nutraceuticals that have been proposed as therapies for obesity and associated metabolic disorders. Functional foods are not specifically addressed. Each section of the chapter is divided into an evaluation of the “proof of concept” studies that purport to demonstrate efficacy, an examination of the claimed modes and mechanisms of action of each nutraceutical and, where available, a brief discussion of any identified key adverse effects. Nutraceutical agents covered include: curcumin, Lagenaria siceraria (bottle gourd), Trigonella foenum-graecum (fenugreek), Emblica officinalis (Indian gooseberry), Murraya koenigii (curry tree), Vigna sp. (black gram), Camellia sinensis (tea), Hibiscus sabdariffa, Hypericum perforatum (St. John’s wort), avocado, capsicum, and rosemary. While potential nutraceutical products and ingredients continue to be a frequent source of “proof of concept” scientific publications, high-quality human clinical trial data are often lacking. Substantial translational scientific work is still needed for many nutraceuticals in terms of assessing their safety properties and demonstrating their efficacy in humans.
Article
Obesity is a worldwide epidemic and is one of the factors involved in the etiology of type 2 diabetes mellitus. Obesity induces low‐grade inflammation and oxidative stress. The treatment for obesity involves changes in diet, physical activity, and even medication and surgery. Currently, the use of nutraceutical compounds is associated with health benefits. Ginger and avocado are used for many people all around the world; however, its effect as a nutraceutical compound is less known by the general population. For this reason, we searched information of the literature to point its effects on distinct mechanisms of defense against the obesity its comorbidities. The present review aimed showing that these nutraceuticals may be useful in obesity treatment. Reports have shown that ginger and avocado induce antioxidant and anti‐inflammatory effects by improving enzymatic activity and modulating obesity‐related impairments in the anti‐inflammatory system in different tissues, without side effects. Furthermore, ginger and avocado were found to be effective in reversing the harmful effects of obesity on blood lipids. In conclusion, on the basis of the positive effects of ginger and avocado in in vitro, animal, and human studies, these nutraceuticals may be useful in obesity treatment.
Article
Full-text available
Poloxamer 407 (P-407) induces hyperlipidemia in the rat. It was the purpose of this investigation to determine if chronic P-407 administration would produce atherogenic arterial lesions in the C57BL/6 mouse, a strain reported to be susceptible to hyperlipidemia-induced atherosclerotic plaque formation. One injection (i.p.) of P-407 (0.5g/kg) produced hypercholesterolemia in the mouse that peaked at 24 h and returned to control levels by 96 h following treatment. Four groups of mice were maintained: (1) saline injected (C); (2) P-407-injected (0.5g/kg every 3rd day) (P); (3) P-407 injected plus cholic acid in the diet (PC); and (4) mice fed a high cholesterol (CHOL) diet containing cholic acid (HF). Mice from each group were sacrificed following 90, 145, 200, or 300 days of treatment. Plasma lipid concentrations, hepatic CHOL concentrations (145 and 300 day), and aortic atherogenic lesion areas were measured. Plasma CHOL and triglyceride remained at control levels throughout the 300 days in the C group. CHOL of the HF animals plateaued at approximately 225 mg/dl. P-407 produced CHOL concentrations of 600 mg/dl in P mice and 1000-1500 mg/dl in PC animals. There was no lesion formation in C mice. However, by 90 days lesions were present in the three other groups. Size of the lesions progressed through day 300 with the largest lesions (184.33 + 27.99 mu2 x 10(-3)) being present in the PC mice. HF and P animals had lesions of 70.50 + 11.35 and 43.33 + 7.88 mu2 x 10(-3), respectively. This study provides an animal model where atherogenesis has been produced with hyperlipidemia induced using a chemical agent.
Article
Full-text available
We investigated the effects of cholesterol, cholestyramine, and taurocholate feeding on steady state specific activities and mRNA levels of hepatic 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase and cholesterol 7 alpha-hydroxylase in the rat. Interruption of the enterohepatic circulation of bile acids (cholestyramine feeding) increased total HMG-CoA reductase activity 5-fold. Cholesterol and taurocholate administration suppressed total microsomal HMG-CoA reductase activities 87% and 65%, respectively. HMG-CoA reductase mRNA levels increased 3-fold with cholestyramine, did not decrease significantly with cholesterol feeding, but were markedly decreased after taurocholate treatment. Cholesterol 7 alpha-hydroxylase activity increased 4-fold with cholestyramine and 29% during cholesterol feeding, but decreased 64% with taurocholate. Cholesterol 7 alpha-hydroxylase mRNA levels rose 150% and 50% with cholestyramine and cholesterol feeding, respectively, but decreased 73% with taurocholate. The administration of cholesterol together with taurocholate prevented the decline in cholesterol 7 alpha-hydroxylase mRNA levels, but inhibition of enzyme activity persisted (-76%). Hepatic microsomal cholesterol concentrations increased 2-fold with cholesterol feeding but did not change with taurocholate or cholestyramine treatment. These results demonstrate that mRNA levels of HMG-CoA reductase are controlled by the hepatic taurocholate flux, whereas mRNA levels of cholesterol 7 alpha-hydroxylase are controlled by the cholesterol substrate supply. These end products, cholesterol and bile acids, exert post-transcriptional regulation on HMG-CoA reductase and cholesterol 7 alpha-hydroxylase, respectively.
Article
The ethnomedical uses of some plants of Asteraceae family used in Nigerian traditional medicine are documented. The members of the family are easily recognised and popular among the traditional doctors. The properties acclaimed for some of the plants tend to agree with those reported in the literature.
Article
The experiment was designed to elucidate the effects of feeding four dietary oils (corn, hazelnut, olive, and fish), and cholesterol supplementation on plasma, liver lipids, and aortic smooth muscle response to drugs. Male Sprague Dawley rats were fed semipurified diets containing one of the above oils (15% wt/wt), either with or without cholesterol supplementation (1% wt/wt), for 20 days. Hazelnut oil-fed rats showed the highest plasma total cholesterol level, while animals fed fish oil exhibited the lowest plasma total and high density lipoprotein cholesterol concentrations. Hepatic cholesterol content was not affected by dietary oils. Liver lipids increased when dietary cholesterol was added to any of the oils used. Acetylcholine pD2 was elevated in fish oil- and hazelnut oil-fed rats, but rats fed all dietary oils showed maximal relaxation. Cholesterol supplementation reduced aortic maximal relaxation caused by acetylcholine. These results indicate that the type of dietary oil and cholesterol intake differentially raise plasma and liver lipid levels and modulate aortic smooth muscle response in the rat.
Article
A Consensus Development Conference on the Health Implications of Obesity was held in February 1985 at the National Institutes of Health in Bethesda, Maryland, USA. After presentations by 19 experts in relevant subject areas, a panel of 15 impartial senior level professionals presented their consensus of findings and recommendations. This paper summarizes the results of the conference and provides reference tables of body mass index (BMI) values and weight goals, along with nomograms of the BMI determined from height and weight scales, to show comparisons with weight goals. The goals are taken from two widely available tables of mortality data by weight. These reference aids are included to illustrate the potential clinical value of wider use of the BMI, as recommended in the conference.
Article
As the twentieth century draws to a close, it is clear that cardiovascular disease (CVD) has become a ubiquitous cause of morbidity and a leading contributor to mortality in most countries.1 2 The rise and recent decline of the CVD epidemic in the developed countries have been well documented.3 4 The identification of major risk factors through population-based studies and effective control strategies combining community education and targeted management of high risk individuals have contributed to the fall in CVD mortality rates (inclusive of coronary and stroke deaths) that has been observed in almost all industrialized countries. It has been estimated that during the period 1965 to 1990, CVD related mortality fell by ≈50% in Australia, Canada, France, and the United States and by 60% in Japan.1 Other parts of Western Europe reported more modest declines (20% to 25%). The decline in stroke mortality has been more marked compared with the decline in coronary mortality. In the United States, the decline in stroke mortality commenced nearly two decades earlier than the decline in coronary mortality and maintained a sharper rate of decline. During the period 1979 to 1989, the age-adjusted mortality from stroke declined, in that country, by about one third, whereas the corresponding decline in coronary mortality was 22%.4 5 In Japan, where stroke mortality outweighs coronary mortality, the impressive overall decline in CVD mortality is principally contributed by the former. The discordant trend of rising CVD mortality rates in Eastern Europe, however, is in sharp contrast to the decline in Western Europe.1 The emergence of the CVD epidemic in the developing countries during the past two to three decades has attracted less comment and little public health response, even within these countries. It is not widely realized that at present, the developing countries …
Article
A previous study demonstrated that a dietary treatment of young geese with cholesterol and cholic acid raises lipid concentrations in the liver. The present study was carried out to investigate whether such a lipid accumulation caused by those hyperlipidemic compounds can be intensified by low dietary choline concentrations. Therefore, 38 eight-week old geese were divided into four groups of 9 or 10 animals each and received a basal diet poor in choline which consisted predominately of maize and soy protein isolate over a period of 8 weeks. Treatment factors were supplementation of diets with cholesterol and cholic acid (0 vs. 5 g of cholesterol and cholic acid each per kg) and supplementation of choline chloride (0 vs. 1.5 g/kg). Final body weights as well as carcass weights were neither influenced significantly by dietary treatment with cholesterol and cholic acid nor by low dietary choline concentrations. However, feeding diets supplemented with cholesterol and cholic acid markedly increased liver weights (two-fold), hepatic triglyceride (3.7-fold) and cholesterol (12-fold) concentrations and percentages of monounsaturated fatty acids at the expense of saturated and polyunsaturated fatty acids in the liver. In geese fed diets with cholesterol and cholic acid, insufficient choline supply did not intensify, but even slightly reduced hepatic lipid accumulation. Geese fed diets with cholesterol and cholic acid exhibited markedly increased levels of cholesterol, triglycerides and phospholipids in plasma and very low-density lipoproteins, regardless of the choline supply. Muscle tissue of geese fed diets supplemented with cholesterol and cholic acid exhibited also increased concentrations of triglycerides and cholesterol whereas the fatty acid composition of muscle lipids remained unchanged. Among geese without hyperlipidemic treatment, concentrations of triglycerides in plasma and very low-density lipoproteins as well as the concentrations of phosphatidylcholine in liver and muscle tissue were not reduced by low dietary choline concentrations. Therefore, it is suggested that those animals were able to synthesize endogenous sufficient choline.
Article
This study investigated the potential alteration in the amount of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase messenger RNA (mRNA) and lipoprotein lipase (LPL) mRNA in the livers of C57BL/6 mice after long-term (200 days) treatment with the nonionic surfactant called poloxamer 407 (P-407). Previously, P-407 has been used to produce a dose-controlled hyperlipidemic state in C57BL/6 mice with subsequent formation of atherosclerotic lesions. Five groups of mice were studied; controls (C); mice fed a standard chow diet enriched with only cholic acid (CH); mice fed the high-cholesterol, high-fat Paigen diet (HF); mice treated with 0.5 g/kg P-407 every third day (P); and mice administered 0.5 g/kg P-407 every third day while consuming a diet identical to that of mice in group CH (PC). Neither a significant (p < 0.05) weight loss nor alteration in liver enzymes (AST and ALT) were observed for any group throughout the study when compared with the control mice. Total plasma cholesterol (CHOL) was significantly elevated compared with controls for mice in groups HF, P, and PC, whereas total plasma triglycerides (TG) were significantly increased for mice in only groups P and PC. Long-term ingestion of a high-fat diet or a diet enriched in cholic acid resulted in a significant (p < 0.05) reduction in HDL-CHOL when compared with controls. Plasma samples assayed at 200 days for mice in groups HF and P showed a shift in the lipoprotein fraction distribution primarily to VLDL-CHOL as compared with mice in group C in which, as expected, most of the CHOL was contained in the HDL fraction. The biologic activity of HMG-CoA reductase assayed in hepatic microsomal homogenates was significantly reduced for mice in groups CH (p < 0.01), HF (p < 0.01), and PC (p < 0.05), but not for mice in group P, when compared with control. A statistical analysis of the data demonstrated significant (p < 0.05) reductions in the HMG-CoA reductase mRNA levels in hepatic tissue for all treatment groups relative to mRNA levels determined for mice in group C. In contrast, no treatment group demonstrated a significant difference in hepatic LPL mRNA levels when compared with mRNA levels determined for control animals. These data demonstrate that P-407 administration to C57BL/6 mice significantly decreased the amount of HMG-CoA reductase mRNA detected in liver.