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All content in this area was uploaded by Marcela Hernández-Ortega on Jan 25, 2016
Content may be subject to copyright.
ORIGINAL PAPER
Hypolipidemic Effect of Avocado (Persea americana Mill)
Seed in a Hypercholesterolemic Mouse Model
María Elena Pahua-Ramos & Alicia Ortiz-Moreno &
Germán Chamorro-Cevallos &
María Dolores Hernández-Navarro &
Leticia Garduño-Siciliano &
Hugo Necoechea-Mondragón &
Marcela Hernández-Ortega
Published online: 2 March 2012
#
Springer Science+Business Media, Inc. 2012
Abstract Avocado seed contains elevated levels of pheno-
lic compounds and exhibits antioxidant properties. We in-
vestigated the effect of Avocado Seed Flour (ASF) on the
lipid levels in mice on a hyperlipidemic diet. The concen-
tration of phenols was determined by high-performance
liquid chromatography, antioxidan t activity was evaluated
using the Trolox equivalent antioxidant capacity method,
and dietary fiber was measured using the Association of
Official Analytical Chemists (AOAC) method. The LD
50
of ASF was determined using Lorke’s method and hypolipi-
demic activity was evaluated in a hypercholesterolem ic
model in mice. Protocatechuic acid was the main phenolic
compound found in ASF, followed by kaempferide and
vanillic acid. The total phenolic content in the methanolic
extract of ASF was 292.00±9.81 mg gallic acid equivalents/
g seed dry weight and the antioxidant activity resulted in
173.3 μmol Trolox equivalents/g DW. In addition, a high
content of dietary fiber was found (34.8%). The oral LD
50
for ASF was 1767 mg/kg body weight, and treatment with
ASF significantly reduced the levels of total cholesterol,
LDL-C, and prediction of the atherogenic index. Therefore,
the antioxidant activity of phenolic compounds and dietary
fiber in ASF may be responsible for the hypocholesterole-
mic activity of ASF in a hyperlipidemic model of mice.
Keywords Avocado
.
Dietary
.
Fiber
.
Hypolipidemic
.
Phenolic compounds
.
Seed
Abbreviations
ABTS 2, 2′-azino-bis (3-ethylbenzthiazoline-6-
sulphonic acid)
AI Atherogenic Index
ASF Avocado Seed Flour
BW Body Weight
Plant Foods Hum Nutr (2012) 67:10–16
DOI 10.1007/s11130-012-0280-6
M. E. Pahua-Ramos
:
A. Ortiz-Moreno (*)
:
M. Hernández-Ortega
Departamento de Ingeniería Bioquímica,
Escuela Nacional de Ciencias Biológicas,
Instituto Politécnico Nacional,
Plan de Ayala y Prol. Carpio s/n, Col. Casco de Santo Tomás,
C.P. 11340 México, D.F., Mexico
e-mail: ortizalicia@hotmail.com
G. Chamorro-Cevallos
:
L. Garduño-Siciliano
Departamento de Farmacia,
Escuela Nacional de Ciencias Biológicas,
Instituto Politécnico Nacional,
Av. Wilfrido Massieu s/n, esq. Manuel L. Stampa,
Col. Unidad Profesional Adolfo López Mateos,
Del. Gustavo A. Madero,
C.P. 07738 México, D.F., Mexico
M. D. Hernández-Navarro
Departamento de Farmacia, Facultad de Química,
Universidad Autónoma del Estado de México,
Paseo Colón esq. Paseo Tollocan, Col. Residencial Colón,
C.P. 50120 Toluca, Estado de México, Mexico
H. Necoechea-Mondragón
Coordinación de Operación de Redes de Investigación,
Instituto Politécnico Nacional,
Edificio Secretaría Académica. Av. Miguel Othón
de Mendizábal s/n, Col. La Escalera,
C.P. 07738 México, D.F., Mexico
GAE Gallic Acid Equivalents
HDL-C High-Density Lipoprotein Cholesterol
LDL-C Low-Density Lipoprotein Cholesterol
LD
50
Median Lethal Dose
TC Total Cholesterol
TG Triglycerides
Trolox 6-hydroxy-2, 5, 7, 8 tetramethylchroman-
2-carboxylic acid
Introduction
The treatment of hypercholesterolemia and related car-
diovascular diseases with medicinal plants has increased
in recent years [1]. Reasons for the increased populari ty
of these herbal medicines may include their relatively
low cost compared to orthodox medicines, availability
(since they are almost always d erived from available
plants in the local region), and efficacy. Although poisonous
plants are ubiquitous throughout the world, herbal medicine is
still used by up to 80% of the total population in developing
countries. Despite widespread use, few scientific studies have
explored the safety and efficacy of traditional herbal remedies
[2] Substances such as chlortalidone and propranolol, which
are used in the treatment of hypercholesterolemia, can have
adverse effects that affect therapy compliance and total quality
of life of the patient [3].
Cardiovascular disease is a growing health problem
throughout the world and represents a leading cause of
mortality a nd morbidity in humans [4]. Several factors,
such as a high caloric diet, age, lack of exercise, smok-
ing, alcohol consumption, and genetic predisposition
have been linked with cardiovascular disease [1]. Elevat-
ed cholest erol levels predispose patients to a condition
known as hypercholesterolemia [5], which in cre ases th e
risk of fatal and nonfatal coronary heart disease in people
over the age of 50 [6].
Several beneficial medicinal proper ties o f compoun ds
present in the avocado seed and peel have been reported,
which are related to the elevated levels of phenolic com-
pounds (64% in seed, 23% in peel, and 13% in pulp). In
addition, the seeds and peels of avocado also contribute
57% and 38% of the antioxidant capacities of the entire
fruit, respectively [7].
Several studies on the hypolipidemic effects of the
avocado seed have been focused on methanolic extracts
[1] and aqueous extracts [8]; howe ver, the study of the
hypolipidemic effects of the entire avocado seed provides
an interesting alternati ve, since the seed represents 13-18%
[9] of the av oc ado fruit and is disca rd ed during avocado
pulp processing. Therefore, the aim of this study was to
investigate the effect of ASF on the lipid levels of mice
on a hyperlipidemic diet.
Materials and Methods
Seed Flour Preparation
Fresh seeds of Persea americana Mill were obtained from an
orchard in Uruapan, Michoacán, Mexico. The seeds were
identified and authenticated with the number 15658 at the
herbarium of the Centro Médico Nacional of the Instituto
Mexicano del Seguro Social. The seeds were washed, cut into
small pieces, and dried in an oven (Fisher Scientific, Isotemp
model 718F, USA) at 40 °C for 48 h until achieving a moisture
level of 4%. The small pieces were then crushed into powder
with a hammer (Wiley Mill standard model No. 3, Arthur
Thomas Co., USA) until the flour passed through US 20 mesh
(0.844 mm).
Phenol Extraction
Phenol extraction was performed according to the method
described by Asaolu et al. [1]. One hundred grams of seed
flour were sloped into a beaker and then extracted with 75%
methanol overnight in a soxhlet extractor (Electro thermal
model ME466, England). The methanolic extract was con-
centrated and allowed to evaporate to dryness at 50 °C using
a rotary evaporator (Büchi 461, Brinkmann Instruments,
Switzerland). The extract was then dissolved in water at a
concentration of 4 g/100 ml.
Total Phenolic Content
HPLC-PDA Analysis of Phenolic Compounds
Twenty microlitres of the methanolic extract were analyzed
using an HPLC-PDA system (Varian 920-LC) and a C18
column (Onmisher 5; 150×4.6 mm i.d.). The solvent mixture
system contained a mixture of 5% formic acid in water (A) and
100% methanol (B), with a flow rate of 0.9 ml/min, and the
gradient flow was as follows: 0 min—5% B; 3 min—15% B;
13 min—25% B; 25 min—
30%B;35min—3
5
%B;39min—
45% B; 42 min—45%B;44min—50% B; 45 min—70% B;
50 min—70%B;56min—75% B; and 61 min—80% B.
Detection was achieved with a photo diode array detector.
Spectrophotometric data from all peaks were monitored at
220–280 nm and chromatograms were recorded at 340 nm.
The data were processed with Varian Galaxie™ Chromatogra-
phy Data Software version 1.9.302.952 (Agilent Technologies
USA). Phenolic compound quantification was determined
using the retention times and absorbance recorded in the
chromatograms relative to external standards [10].
Total phenol content was quantified using the Folin
Ciocalteu [11]. G allic acid was used as a standard for the
calibratio n c ur ve. The result s w ere expressed as gallic
acid eq uiva lents (GAE) m g/g seed dry weight (D W) .
Plant Foods Hum Nutr (2012) 67:10–16 11
Antioxidant Activity
Total antioxidant capacity was evaluated using the method
reported by Re et al. [12] with Trolox as the standard. A
stock solution was prepared by reacting 7 mM ABTS with
2.45 mM potassium persulfate to generate the ABTS cation
chromophore. This solution was diluted with absolute
ethanol until reaching an absorbance of 0.7±0.02 at
734 nm. A sample of 10 μl of ASF extract was added
to 990 μL of ABTS solution and the reaction was followed
over a 7 min time course. Total antioxidant activity or capacity
was calculated relative to the reactivity of Trolox as the
standard under the same conditions. The results were
expressed as μmol Trolox equivalent/g of seed DW.
Proximate Analysis
Moisture, protein, ether extract, ash, and crude fiber
content in ASF were determined in triplicate following
the standard methods from the Association of Official
Analytical Chemists International (AOAC) [13], and total
carbohydrate content was calculated as the difference to a
total of 100%. Dietary fiber was also determined in
triplicate using AOAC methods 997.08 and 999.03 [13].
Animals
For the hypolipidemic activity assay, 40 8-10-week-ol d
adult male CD-1 mice with an average weight of 28±2 g
were obtained from the Centro de Investigac ión y Estudios
Avanzados (CINVESTAV) at the Instituto Politécnico Nacional
(IPN-México). Each mouse was weighed and random ly
assigned to groups by body weight (BW). Each group of mice
was housed in cages with wooden chip bedding and maintained
under a 12 h light/dark cycle. Mice were fed with standard
laboratory chow (5001 Lab Rodent Diet, PMI Nutrition
International, Inc., Bienwood, MO) and provided water
ad libitum. The animal experiments and study design
were approved by the Laborato ry Animal Care Commit-
tee of IPN and wer e conducted in compliance with the
Official Mexican standard NOM-062-ZOO-1999 regarding
technical specifications for production, care, and use of labo-
ratory animals [14].
Oral Acute Toxicity
Acute toxicity tests were conducted according to Lorke’s
methodology [15].
Hypolipidemic Activity of ASF
Five groups of CD-1 mice (8 mice per group) were formed,
with group 1 serving as the control. A diet rich in cholesterol
was supplied to the animals ad libitum for six days in
order to induce hypercholesterolemia [ 16, 17]. The diet
formula u sed is shown i n Table 1.Group2–5 recei ve d
the hypercholesterolemic diet, which was administered
with distilled wate r (group 2 ) or differen t dose s of ASF
(groups 3, 4 and 5 received 125, 250, and 500 mg ASF/kg
BW, respectively, once a day) by gavage. The doses were
chosen according to the acute toxicological study divided by a
security factor of 10.
At the end of six days, the TC, HDL-C, LDL-C and TG
concentrations were determined according to the methodology
described by Argüelles et al. [17].
Statistical Analysis
All data for acute toxicity were statistically analyzed by the
Student’s t-test using Sigma-Stat version 3.5 (Jandel San
Raphael, CA) and P <0.001 was considered statistically
significant. Hypolipide mic activity data were s tatisticall y
analyzed by one-way analysis of varia nce (ANOVA) and
Tuk
ey’s test using Sigma-Stat version 3.5 (Jandel San
Raphael, CA). The data were reported as mean ± standard
deviation (SD). A P <0.05 was considered statistically
significant for hypolipidemic activity data.
Results and Discussion
Identification of Phenolic Compounds
Analysis of methanolic extract from avocado seed by
HPLC-PDA identified eleven major peaks. Seven phe nolic
compounds were identified using external standards, spectra
characteristics, and retention time. Protocatechuic acid
(128.18±0.01 μg/g DW) was the main phenolic compound
identified, followed by kaempferide (107.42±0.04 μg/g
DW) and vanillic acid (28.67 ±0.001 μg/g DW). In addition,
clorogenic acid, syringic acid, rutin, and kaempferol were
present in small amounts (Table 2). Recen tl y, Rodrígu ez-
Carpena et al. [18] analyzed and classified phenolic
compounds from two avocado varieties as ca techins,
(sum of catechin and ep icate c hin) , hydroxybenzoi c acids
Table 1 Formulation
for the hypercholesterol-
emic diet
Ingredients % of total weight
Lab rodent diet
5001
53.5
Sucrose 30
Casein 10
Butter 5
Cholesterol 1
Sodium cholate 0.5
12 Plant Foods Hum Nutr (2012) 67:10–16
(p -coumaric, caffeic, ferulic, and sinapic), hydroxycin-
namic acids (p-hydroxybenzoic, protocatechuic, vanillic,
syringic, and gallic), flavonols, and procyanidins (sum of
dimers, oligomers, and polymers). These authors r eported
that the seed and peel contained the highest amount of
phenols in the entire fruit. Moreover, Terpinc et al. [19]
reported that flavonoids, rutin, catechin, and quercetin
are widespread in nature and may act as powerful
antioxidants.
These findings and our results provide evidence for the
importance of phenols present in avocado seed, since
phenolic compounds have been shown to reduce plasma
lipid levels in human body through the upregulation of
LDL receptor expression, inhibition of hepatic lipid synthesis
and lipoprotein se cretion, a nd incre ase i n c holesterol
elimination through bile acids [20].
Total Phenolic Content and Antioxidant Activity of ASF
The total phenolic content and antioxidant activity of the
methanolic extract of ASF was determined to be 292.00±
9.81 mg GAE/g seed DW and 173.3 μmol Trolox equiv-
alents/g seed DW, respectively. Rodríguez-Carpena et al.
[18] previously reported a total phenolic content of 351.1±
9.88 mg GAE/g seed for t he Hass variety and 416.4±
10.48 mg GAE/g seed dry matter for the Fuerte variety.
According to Wang et al. [7], seeds contain the strongest
antioxidant properties and highest phenol and procyanidin
content compared to the pulp. Soong & Barlow [21 ]
reported a s ignificantly higher total antioxidant capacity
and phenolic content of fruit seeds than the edible portions.
In most fruits, the contribution of the fruit seed fraction
compared to the total antioxidant activity and phenolic
content was more than 95%, and therefore these authors
suggested that the fruit seeds should be further utilized
rather than just discarded as waste [21]. Importantly, our
results are in agreement with the findings by Wang et al.
[17] and Soong & Barlow [21] showing that the antioxidant
activity of fruit seeds components may be responsible for
the hypocholesterolemic activity observed.
Proximate Analysis and Dietary Fiber
We found that the ASF preparation contained 4.0±0.8
moisture, 2. 2±0.14 ash, 4.75±0.01 protein, 6.39±0.5
crude fiber, 4.38±0.8 ether extract, and 79.10±0.8 car-
bohydrates (data expressed as mean ± standard deviation
g/100 g sa mple fresh weight; n0 3). The low oil content
of the ASF suggested that oil and its fatty acids could
have a minimal effect on cholesterol and LDL-C reduc-
tion, since i t only represented a small portion of t he total
daily oil intake of the treated mice. Nijjar et al. [22]
found t hat nuts a re a good source of mono and pol y-
unsaturated fatty acids and also contain dietary fiber,
phytosterols, and polyphenols. These components likely
combine to a reduction in LDL-C levels beyond the
effects predicted by equations based solely on fatty acid
profiles. Nevertheless, the high crude fiber content
(6.39 g/100 g DW sample) of ASF could have a beneficial
effect on total cholesterol and LDL-C reduction in the
plasma of the g roups of mice treated [23].
The ASF preparation was found to contain 34.8±3.4 g
dietary fiber/100 g DW samp le, which is relevant in this
study, since the natural gel-forming or viscous fibers
(pectin, gums, mucilage, algal polysaccharid es, some
storage polysaccharides, and some hemicelluloses) are
water-soluble and resistant to digestion by human gastro-
intestinal enzymes that are part of the dietary fiber.
Moreover, this content has been shown to be associated
with a cholesterol-lowering effect [24]. The dietary fiber
content of the avocado seed is similar to another Mexican
seed called chia [25
]. Reyes-Caudillo et al. [25]r
e
portedthat
chia seeds from Jalisco and Sinaloa States contain a total
dietary fiber content of 39.9% a nd 36.9%, respectively.
Therefore, the die tary fibe r conte nt in chia see ds is of
sufficient level to promote beneficial health effects,
including a reduction of cholesterolaemia, modification of
the glycemic and insulinaemic responses, changes in intestinal
function, and antioxida nt a ctivity. The high content of
dietary fiber in ASF found in the present study
suggests that dietary fiber could play an important role in
the hypocholesterolemic activity in mice.
Oral Acute Toxicity
In the first stage of the oral acute toxicity study, the
animals did not exhibit any toxicological signs, including
depression, writhing, diarrhea, hypermotility, or aggression
Table 2 Phenolic compounds in methanolic extract from Persea
americana Mill
Peak number Rt (min) UV (nm) μg/g
1 Protocatechuic acid 6.12 243, 322 128.18±0.01
2 Clorogenic acid 7.37 242,278,439 0.516±0.02
3 Syringic acid 8.98 242,314, 443 2.51±0.002
4 Vanillic acid 9.87 242,380,436 28.67±0.001
5 NI 11.00 242,307,446 –
6 Rutin 11.67 242,277,319,386 9.63±0.008
7 NI 13.28 242,315,363 –
8 NI 14.48 242,318,446 –
9 Kaempferol 16.30 242,311,386,429 2.19±0.002
10 Kaempferide 23.81 216,242 107.42±0.04
11 NI 51.71 241,334,380 –
Data expressed as mean ± standard deviation; n0 3. NI0 not identified
Plant Foods Hum Nutr (2012) 67:10–16 13
compared to the control group. No signs of toxicity or death
were observed in any of the animals, and all animals survived
to the end of the 14 day study period. Weight gain in the
control animals was minimal (< 4%), while the treated
animals exhibited a slight increase in w eight, although
there was no significant difference in the percent weight
change between the groups (P<0.05). In the s ec on d stage
of the study, we observed 100% mortality by day six in
the group fed with 2500 mg ASF/kg BW. Table 3 lists
the effects of different doses of ASF on daily food and
water intake and on the weight of the main organs,
which was exp res sed as a ratio of r elati ve w eig ht ( RW)
to total body weight. Mice administered 100 and
1000 mg ASF/kg BW exhibited significant differences
(P ≤ 0.001) com pared with the control, where by liver
weight was lower and kidney weight was higher than
control group. An increase in the RW of the kidney has
also been reported by Ozolua et al. [8] in adult rats fed
aqueous seed extract from avocado. In addition, Brai et al.
[26] found that liver weights were significantly increased in
albino rats fed avocado aqueous leaf extract after induction of
a hyperlipid em ic di et compared to normal cont rol r at s,
which was accompanied with a significant increase in
liver cholesterol level. These findings together with the
results of this study sugges t that the comp ound s pre sent
in avocado leaves and seeds are different and have an
opposite influence on the liver.
In the second stage of the acute toxicity study, no significant
differences (P>0.001) were found in daily food and water
intake between mice treated with 1250 mg ASF/kg BW and
control mice; however, significant differences (P≤ 0.001)
were found in daily food and water intake between mice
treated with 2500 mg ASF/kg BW and control mice.
Based on these results, we determined the oral LD
50
for
ASF to be 1767 mg/kg BW by using the geometric mean of
the dose tha t cau sed 100 % m ortality and the dose that
caused no mortality, as suggested by Lorke [15]. The oral
LD
50
of ASF in mice indicated that it exhibited a low
toxicity [17]. It has previously been shown that ether
and aqueous extracts of Persea americana Mill seed
administered by intraperitoneal injection in rats also had
low toxicity, with LD
50
values of 751.6 mg/kg BW an d
10 g/kg BW, respectively [8 , 27].
Hypolipemic Activity of ASF
To determine the hypolipemic activity of ASF, mice were
dosed according to the LD
50
of ASF found in this study. The
Table 3 Daily food and water consumption and relative weight of liver and kidney in CD-1 mice treated with different doses of avocado seed flour
Groups Dose (mg/kg) Daily food consumption (g) Daily fluid consumption (ml) LBW (%) KBW (%)
Control 1st step
a
– 38.3±10.2 40.8±12.8 6.80±0.15 1.58±0.09
ASF 10 28.4±10.4
a
34.4±14.3 6.75±0.37 2.67±0.02
a
100 31.9±8.3 47.1±11.2 5.48±0.11ª,
b
1.83±0.05
a,b
1000 33.7±7.3 50.2±10.4
a
5.04±0.22ª,
b
1.75±0.09
a,b
Control 2nd step
c
– 35.5±6.2 53.4±9.7 5.50±0.28 1.54±0.16
ASF 1250 40.8±8.0 46.9±7.6 5.14±0.14 1.44±0.10
2500 21.3±14.5
c
28.1±15.8
c
ND ND
Data expressed as mean ± standard deviation; n0 8. ASF, Avocado Seed Flour; LBW, liver-to-body weight ratio; KBW, kidney-to-body
weight ratio.
a
P<0.001, significant difference with respect to control 1st step,.
b
P<0.001; significant difference with respect to 10 mg/kg of ASF;
c
P<0.001, significant difference with respect to control 2nd step. ND: Not determined.
Table 4 Effect of avocado seed flour on lipid profile of mice
Treatment ASF Dosis (mg/kg) TC (mmol/L) LDL-C (mmol/L) HDL-C (mmol/L) TG (mmol/L) AI
Normocholesterolemic – 31.9±7.16 12.50±3.02 18.92±4.25 1.05±0.13 1.6±0.05
Hypercholesterolemic – 106.7±9.70 92.1±10.26 15.00±2.1 0.852±0.09 7.9±1.86
ASF 125 70.9±4.49
a
55.8±5.35
a
15.6±1.79 0.872±0.09 3.9±0.59
a
250 69.0±5.15
a
56.1±5.28
a
13.5±0.78 0.914±0.07 4.3±0.58
a
500 67.6±4.92
a
54.4±5.37
a
13.8±1.21 0.930±0.12 4.3±0.72
a
Data expressed as mean ± standard deviation; n0 8, analyzed by ANOVA and Tukey-Kramer test.
a
P≤ 0 .0001; significant difference with
respect to the hypercholesterolemic control. ASF, Avocado Seed Flour. TC, Total Cholesterol; LDL-C, Low-density Lipoprotein
Cholesterol; HDL-C, High-density Lipoprotein Cholesterol; TG, Triglycerides; AI, Ath erogenic Index.
14 Plant Foods Hum Nutr (2012) 67:10–16
hypolipidemic effect of ASF was evaluated at doses at 125,
250, and 50 0 mg/kg BW. Acute supplementation of
cholesterol produced a significant (P≤ 0.05) elevation in
plasma cholesterol levels in the hypercholesterolemic
control compared to the normocholesterolemic control.
In addition, the TC increa sed from 31.9±7.16 to 106.7±
9.70 mmol/L, LDL-C increased from 12.5±3.02 to 92.1±
10.26 mmol/L, and the calculated AI increase from 1.6±
0.05 to 7.9±1.86 between the two groups, respectively
(Table 4 ). No significant (P>0.05) changes were found
in the plasma HDL-C (18.92±4.25 vs 15.0±2.1 mmol/L,
respectively) and TG (1.05±0.13 vs. 0.85±0.09 mmol/L,
respective ly) between the two groups. These o bse rvat ions
could be associated with insulin activit y [28].
Similar results were reported by Asaolu et al. [1]in
normocholesterolemic and hypercholesterolemic groups for
TC (3.12±0.83 mmol/L vs 7.52±1.11 mmol/L, respectively)
andLDL-C(0.36mmol/Lvs5.79±2.10mmol/L,respec-
tively) using a methanol extract of avocado seeds. In
addition, t he AI was significantl y increased in the hyper-
cholesterolemic group compared to the normocholestero-
lemic group of that study (4.3 vs 1.3, respectiv ely) .
Treatment of mice with 125 mg ASF/kg BW significantly
(P≤ 0.05) reduced the elevated levels of TC by 33% (106.7±
9.70 to 70.9±4.49 mmol/L) and LDL-C by 39.4% (92.1±
10.26 to 55.8±5.35 mmol/L). In addition, treat ment with
250 mg ASF/kg BW reduced TC and LDL-C by 34 and
39%, respectively, while treatment with 500 mg ASF/kg
BW reduced the TC and LDL-C levels by 36 and 41%,
respectively. A similar effect was reported by Asa olu et al.
[1] in Albino rats administered 200 mg of avocado seed
extract (75% methanol)/kg BW, where they observed a
significant reduction in TC, LDL-C, and TG levels by 47,
69, and 44%, respectively, compared to hypercholesterolemic
control mice. In addition, it was reported that the cholesterol
levels of hype rt ensiv e rats treated with 5 00 mg/kg BW of
avocado aqueous seed extract were reduced by 19.2,
42.5, 47.9, and 13.6% in the plasma, kidney, heart, and
liver, respectively, compared to hyp e rtens ive control mic e
[29]. In add it ion, significant r ed ucti ons in LDL-C and
triglycerides were also observed. These studies together
with our results indicate that aqueous or methanol seed
extract or seed flour of avocado can be used as an
effective supplement in mice and rats for treating
hyperlipidemia.
Conclusion
In this study, we found that ASF has low toxicity and can
significantly reduce the cholesterol and LDL-C levels in
hypercholesterolemic mice. This effect could be attributed
to the phenolic content, antioxidant activity, and/or dietary
and crude fiber content of the seed. Further research is
required in order to identify the components of ASF that
are responsible for the observed hypocholesterolemic
effects.
Acknowledgments This research was partly funded by the Consejo
Nacional de Ciencia y Tecnología (CONACyT) scholarship, Secretaria
de Investigación y Posgra do-IPN Proyect Number. 20100788,
Comisión de Operación y Fomento de Actividades Académicas del
IPN (COFAA-IPN), and Universidad Autónoma del Estado de México.
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