concentrations of polyunsaturated fatty acids
(PUFAs). In a study done by Dei, Takeda et al.
(2002), an increase of MDA levels with age had been
demonstrated in the cytoplasm of neurons and
astrocytes. To fulfill a high demand of energy, brain
also consumes a large amount of oxygen. However,
compared to other organ, it relatively lacks
antioxidant defenses, such as a lower activity in
glutathione peroxidase and catalase, making it more
vulnerable to oxidative stress. (Kedar, 2003).
Therefore, protecting the brain from excessive
oxidative damage might ameliorate the balance
between pro-oxidants and antioxidants, hence
promoting a healthier aging process.
One preventive effort to ensure this healthy aging
is reflected in phytotherapy, known as herbal
medicine, which utilizes therapeutic potential of a
certain plant (Ho, So et al., 2010). Centella asiatica
(CA), a medicinal tropical plant from the family
Apiaceae used commonly in Southeast Asia, had
shown to have neuroprotective and cognitive-
enhancement effect which could play an important
role in aging (Dev, 2009, Mukherjee, Kumar et al.,
2007, Tiwari, Singh et al., 2008, Veerendra Kumar
and Gupta, 2003). However, there were only a limited
number of researches examining the antioxidative
properties possessed by this plant, especially its role
in brain aging and lipid peroxidation. The animal
subjects which were used was also limited to a single
breed of rat; not to mention the lack of comparison
with a proven exogenous antioxidant.
In the present study, we compared the brain MDA
levels between CA-treated aged Sprague-Dawley rats
and their younger counterparts. The antioxidative
properties of CA on aged rats were also compared to
a well-known antioxidant agent, vitamin E. We
hypothesized that aged rats which were treated with
CA extract would have a lower level of brain MDA
compared to those untreated, thus raising the potential
of CA as an antioxidant which could promote a
healthier aging process.
2 METHODS
2.1 Study Design and Subjects
The subject used in this experiment, the male
Sprague-Dawley rats, is a distinct outbred albino rat
used commonly in nutritional and medical research
settings. These rats were obtained from the National
Institute of Health Research and Development,
Ministry of Health Republic of Indonesia. Sprague-
Dawley rat has an elongated head structure and a tail
longer than its body. These rats are first bred by R. W.
Dawley from the Sprague-Dawley Animal Company
in Wisconsin, United States in 1925. Their docile
characteristics make them easy to handle.
The rats were divided into two groups according
to their age; young rats (8-12 weeks old) and aged rats
group (20-24 months old). The aged rats were further
divided into three final groups according to the
treatment given; negative control (water as placebo),
positive control (vitamin E), and treatment (Centella
asiatica ethanolic leaves extract) group. In total, there
were 4 experimental groups.
To differentiate individual rats in every group, a
color-coding system was used; each rat possessed a
distinct mark on a certain part of its body. The rats
have initial weights ranging from 183 to 308 g for the
young rats, and 333 to 490 g for the aged, all in
healthy state. Using Federer’s formula, a minimum of
24 subjects was needed to achieve the optimal sample
size. However, to anticipate the possibility of subject
exclusion due to death or other unforeseen causes, a
total of 27 rats were used.
2.2 Extract Preparation
Centella asiatica (CA) leaves were dried under the
sunlight until the water content fully evaporated and
grinded to small fractions. The active substances of
these grinded particles were then extracted by soaking
them to a solvent, ethanol, for 24 to 48 hours
repeatedly. To obtain and separate the active
substances from its solvent, a rotary evaporator was
utilized. Subsequently, the percentage of active
substances contained in the viscous solution produced
from this process was measured using gravimetric
analysis.
2.3 Treatments
Prior to the 28-day treatment, all rats underwent a
one-week acclimatization at the experiment room,
adapting to a 24
o
C temperature and a light-dark cycle
of 12:12 with lights on at 9.00 PM. Throughout the
study, all groups were fed daily with 10 g of standard
pelleted chow (protein 18.5-20.5 %; fat ± 4%; fiber ±
6%; calcium ± 0.9%; phosphor ± 0.7%) and provided
with water ad libitum.
After the aged rats were randomly distributed into
the three groups, the following treatment was started
at day-1 and ended at day-28 accordingly; water as
placebo (negative control), CA leaves ethanolic
extract with 300 mg/kg bodyweight dosage
(treatment), and 6 IU of vitamin E (positive control).
All treatments were given twice daily. As for the
BROMO 2018 - Bromo Conference, Symposium on Natural Products and Biodiversity
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