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Artemisia absinthium (AA): A novel potential complementary and alternative medicine for breast cancer

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  • Manipal Academy of Higher Education - Dubai Campus

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Natural products have become increasingly important in pharmaceutical discoveries, and traditional herbalism has been a pioneering specialty in biomedical science. The search for effective plant-derived anticancer agents has continued to gain momentum in recent years. The present study aimed to investigate the role of crude extracts of the aerial parts of Artemisia absinthium (AA) extract in modulating intracellular signaling mechanisms, in particular its ability to inhibit cell proliferation and promote apoptosis in a human breast carcinoma estrogenic-unresponsive cell line, MDA-MB-231, and an estrogenic-responsive cell line, MCF-7. Cells were incubated with various concentrations of AA, and anti-proliferative activity was assessed by MTT assays, fluorescence microscopy after propidium iodide staining, western blotting and cell cycle analysis. Cell survival assays indicated that AA was cytotoxic to both MDA-MB-231 and MCF-7 cells. The morphological features typical of nucleic staining and the accumulation of sub-G1 peak revealed that the extract triggered apoptosis. Treatment with 25 μg/mL AA resulted in activation of caspase-7 and upregulation of Bad in MCF-7 cells, while exposure to 20 μg/mL AA induced upregulation of Bcl-2 protein in a time-dependent response in MDA-MB-231 cells. Both MEK1/2 and ERK1/2 was inactivated in both cell lines after AA treatment in a time-dependent manner. These results suggest that AA-induced anti-proliferative effects on human breast cancer cells could possibly trigger apoptosis in both cell lines through the modulation of Bcl-2 family proteins and the MEK/ERK pathway. This might lead to its possible development as a therapeutic agent for breast cancer following further investigations.
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Artemisia absinthium (AA): a novel potential complementary
and alternative medicine for breast cancer
Gowhar Shafi Tarique N. Hasan Naveed Ahmed Syed
Amal A. Al-Hazzani Ali A. Alshatwi
A. Jyothi Anjana Munshi
Received: 16 May 2011 / Accepted: 25 January 2012
ÓSpringer Science+Business Media B.V. 2012
Abstract Natural products have become increasingly
important in pharmaceutical discoveries, and traditional her-
balism has been a pioneering specialty in biomedical science.
The search for effective plant-derived anticancer agents has
continued to gain momentum in recent years. The present
study aimed to investigate the role of crude extracts of the
aerial parts of Artemisia absinthium (AA) extract in modu-
lating intracellular signaling mechanisms, in particular its
ability to inhibit cell proliferation and promote apoptosis in a
human breast carcinoma estrogenic-unresponsive cell line,
MDA-MB-231, and an estrogenic-responsive cell line, MCF-
7. Cells were incubated with various concentrations of AA,
and anti-proliferative activity was assessed by MTT assays,
fluorescence microscopy after propidium iodide staining,
western blotting and cell cycle analysis. Cell survival assays
indicated that AA was cytotoxic to both MDA-MB-231 and
MCF-7 cells. The morphological features typical of nucleic
staining and the accumulation of sub-G1 peak revealed that
the extract triggered apoptosis. Treatment with 25 lg/mL AA
resulted in activation of caspase-7 and upregulation of Bad in
MCF-7 cells, while exposure to 20 lg/mL AA induced
upregulation of Bcl-2 protein in a time-dependent response in
MDA-MB-231 cells. Both MEK1/2 and ERK1/2 was inacti-
vated in both cell lines after AA treatment in a time-dependent
manner. These results suggest that AA-induced anti-prolif-
erative effects on human breast cancer cells could possibly
trigger apoptosis in both cell lines through the modulation of
Bcl-2 familyproteinsand the MEK/ERK pathway.This might
lead to its possible development as a therapeutic agent for
breast cancer following further investigations.
Keywords Artemisia absinthium Caspase-7 Bad
Bcl-2 MEK/ERK MDA-MB-231 MCF-7
Apoptosis Cancer therapy
Introduction
Artemisia absinthium (AA) is commonly called worm-
wood, and is locally known as ‘Tethwen’ in the Kashmir
Valley, India. It is used in indigenous medicine as a ver-
mifuge, an insecticide, an antispasmodic, an antiseptic, and
in the treatment of chronic fevers and inflammation of the
liver [1]. Its essential oil has antimicrobial [2] and anti-
fungal activity [3]. Chemical analysis of AA extracts has
shown that its volatile oil is rich in thujone, which has been
reported as an anthelmintic [4]. In Turkish folk medicine,
AA has been used as an antipyretic, antiseptic, anthel-
mintic, tonic, diuretic, and for the treatment of stomach-
aches [5].
Breast cancer is the most common oncological disease in
women worldwide, and its incidence and mortality rates
G. Shafi A. Jyothi A. Munshi (&)
Department of Molecular Biology, Institute of Genetics and
Hospital for Genetic Diseases, Osmania University, Begumpet,
Hyderabad 500016, Andhra Pradesh, India
e-mail: anjanadurani@yahoo.co.in
G. Shafi A. Munshi
Dr. NTR University of Health Sciences, Vijayawada,
Andhra Pradesh, India
G. Shafi T. N. Hasan N. A. Syed A. A. Alshatwi
A. Munshi
Molecular Cancer Biology Research Lab (MCBRL),
Department of Food Sciences and Nutrition, College of Food
and Agricultural Sciences, King Saud University, Riyadh,
Saudi Arabia
A. A. Al-Hazzani
Department of Botany and Microbiology,
King Saud University, Riyadh, Saudi Arabia
123
Mol Biol Rep
DOI 10.1007/s11033-012-1569-0
may be explained by differences in the relative risk or
prevalence of risk factors, including dietary factors [6].
However, the efficacy of currently available drugs is very
limited, and anticancer agents that can target multiple points
in the apoptotic cascade to achieve synergistic actions are
urgently required. Chinese herbs have obtained considerable
attention for the prevention and treatment of certain cancer
types in clinical studies [710]. In many cases however,
extracts obtained from plants are not highly effective and
require chemical modification for improved potency and
toxicity profile [1113]. Several phytochemicals that have
been used in clinical cancer chemotherapy were originally
derived from herbs and plants, such as paclitaxel [9,14],
etoposide [15], camptothecin [8] and vinca alkaloids [16].
Thus, studies of naturally-occurring plant-based agents
could lead to the development of new strategies for the
management of cancer and related diseases. Specific com-
pounds in certain foods have been shown to reduce human
breast cancer cell proliferation through apoptosis and cell
cycle arrest [17]. Interestingly, the apoptosis pathway was a
novel target for cancer chemoprevention in recent studies of
several chemopreventive agents [18]. The current study was
designed to investigate the in vitro anticancer activity of
crude extracts of the aerial parts of AA on estrogen-
responsive MCF-7 and estrogen-unresponsive MDA-MB-
231 human breast cancer cell lines.
Materials and methods
Preparation of plant material
Plants were selected on the basis of ethnopharmacology,
and 3 kg of plant material was collected locally. It was
identified by a botanist from the Department of Botany,
Osmania University, and a specimen was deposited at the
herbarium. The aerial parts of AA were air-dried in shade,
then powdered using a milling machine. The powdered
plant material was extracted with methanol as described
previously [19]. Briefly, powdered plant material was
soaked in ten times the volume of methanol for extraction.
Extraction was performed three times, and each extraction
was performed for 24 h. Methanolic filtrate was then
evaporated under reduced pressure to obtain a residue
(500 g of AA yielded 29.15 g of residue). The residue was
dried using a rotary evaporator to obtain the powder/paste,
and the required quantity was dissolved in dimethyl sulf-
oxide (DMSO).
Preparation of drug
A stock of plant extract was prepared to a concentration of
1 mg/mL in DMSO and sterilized by autoclaving at 121°C
and 15 lb for 15 min. Then, five concentrations of test
drug (5, 20, 50, and 100 lg/mL) were prepared by dilut-
ing stock with DMEM. DMEM alone was used as a
vehicle control.
Maintenance of cell lines
MDA-MB-231 and MCF-7 cells were procured from the
National Centre for Cell Science (Pune, India). The cell
lines were maintained and propagated in 90% Dulbecco’s
Modified Eagle’s Medium (DMEM) supplemented with
10% fetal bovine serum (FBS) and 1% penicillin/strepto-
mycin. Cells were cultured as adherent monolayers to
approximately 70–80% confluence, and maintained at 37°C
in a humidified atmosphere of 5% CO
2
. Cells were har-
vested after brief trypsinization. All chemicals used were of
research grade.
Cell toxicity and viability assays
MDA-MB-231 and MCF-7 cells were grown in DMEM at
37°C under 5% CO2 in a humidified incubator. Cells were
harvested, counted and transferred to 96-well plates, and
incubated for 24 h prior to addition of the test compounds.
The extracted compounds were processed and applied in
various concentrations, and the treated cells were incubated
for 72 h. MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-
tetrazolium bromide) (5 mg) was dissolved in 1 mL
phosphate-buffered saline (PBS), and 25 lL MTT solution
was added to each of the wells. The plates were wrapped in
aluminum foil and incubated at 37°C for 4 h. The solution
in each well, containing media, unbound MTT and dead
cells, was removed by suction, and replaced with 200 lL
DMSO. The plates were then shaken, and the optical
density was measured using a microplate reader at 575 nm.
Three independent experiments were performed for each
study and all measurements were performed in triplicate.
Results were expressed as the percentage proliferation with
respect to vehicle-treated cells. Cells were further treated
with IC
50
concentrations of AA (25 lg/mL for MCF-7
cells and 20 lg/mL for MDA-MB-231 cells) or vehicle
(0.1%) for 24, 48 or 72 h.
Apoptotic assays
The apoptotic effects of AA on MDA-MB-231 and MCF-7
cells were analyzed by nuclear DNA staining assays. AA-
treated and untreated cells were fixed in 4% paraformal-
dehyde in PBS for 20 min, washed twice with PBS, and
stained with 1 lg/mL propidium iodide (PI) (Sigma) for
15 min. Stained cells were then washed twice with PBS.
The changes in nuclei were observed under an ultraviolet
fluorescent microscope (Carl Zeiss).
Mol Biol Rep
123
Flow cytometry analysis
MDA-MB-231 and MCF-7 cells in the exponential phase
of growth were treated with AA extract (20 lg/mL for
MDA-MB-231 cells and 25 lg/mL for MCF-7 cells) for 24
and 48 h, then harvested by trypsinization, washed twice
with ice-cold PBS and fixed by 70% ethanol at -20°C for
at least 30 min. The fixed cells were then washed twice
with ice-cold PBS and stained with 50 lg/mL PI for
30 min. Cell cycle distribution was analyzed by using a
FACSCalibur (Becton–Dickinson, USA). Data from
10,000 cells per sample were collected and analyzed using
the Cell Fit Cell analysis program.
Western blot analysis
MDA-MB-231 and MCF-7 cells were grown in 6-well
plates, and when cell density reached 80–90% confluence,
cells were treated with AA (20 lg/mL for MDA-MB-231
cells and 25 lg/mL for MCF-7 cells) for 24, 48 or 72 h.
After treatment, cells were collected and washed twice
with cold PBS. The cells were then lysed in lysis buffer
(50 mM Tris–HCl, pH 7.5, 150 mM NaCl, 1% Nonidet
P-40, 2 mM EDTA, 1 mM EGTA, 1 mM NaVO3, 10 mM
NaF, 1 mM DTT, 1 mM PMSF, 25 lg/mL aprotinin, and
25 lg/mL leupeptin) and kept on ice for 30 min. The lysates
were then centrifuged at 12,0009gat 4°Cfor20minand
the supernatants were stored at -70°C until use. Protein
concentration was determined by the Bradford method.
Aliquots of the lysates (30 lgofprotein)wereseparatedin
12% SDS-PAGE and transferred onto a nitrocellulose
membrane using transfer buffer (192 mM glycine, 25 mM
Tris–HCl, pH 8.8, and 20% methanol [v/v]). After blocking
with 5% non-fat dried milk, the membranes were subse-
quently incubated with the corresponding primary antibod-
ies, as indicated: a rabbit anti-PARP p85 fragment, anti-
active ERK1/2, anti-active MEK1/2 and anti-MEK1/2
polyclonal antibody, a mouse anti-caspase-7, anti-Bcl-2 and
anti-Bad monoclonal antibody, rabbit anti-ERK 1/2 poly-
clonal antibody (Abcam Inc, USA); Antibody recognition
was detected with the respective secondary antibody, anti-
mouse IgG antibodies linked to horseradish peroxidase
(Abcam Inc, USA). Primary antibodies were used at a
1:1,000 dilution, while horseradish peroxidase-conjugated
horse anti-rabbit IgG (Sigma Chemicals, USA) was used at a
1:5,000 dilution as the secondary antibody. The membrane
was then exposed and protein bands were detected using
Enhanced Chemiluminescence (Abcam Inc, USA).
Statistical analysis
The data were expressed as the mean (±SD). Comparisons
between groups were performed by Student’s ttest and
one-way analysis of variance (ANOVA). All statistical
analyses were performed using the statistical software
PASW 18.0. Pvalues of \0.05 were regarded as statisti-
cally significant.
Results
Inhibition of cell proliferation in AA-treated MCF-7
and MDA-MB-231 cells
To investigate the effects of AA methanolic extract on
MDA-MB-231 and MCF-7 cell proliferation, the cells were
treated with various concentrations of AA for 72 h. AA at
25 lg/mL caused almost 50% inhibition of cell prolifera-
tion in MCF-7 cells compared with controls, while 20 lg/
mL caused 50% inhibition in MDA-MB-231 cells with
(Figs. 1,2a, b). The anti-proliferative activity was time-
dependent in both cell types. Therefore, we used respective
concentrations to perform the downstream experiments.
Microscopic signs of apoptosis in AA-treated cells
The ability of AA to alter cell morphology indicative of
apoptosis in the cancer cell lines was assessed using PI
staining (Fig. 3). After incubation for 48 h with AA, the
cells became rounded in appearance, exhibited nuclear
condensation and significant nuclei fragmentation indicat-
ing apoptosis.
Flow cytometry analysis
Cell cycle analysis by flow cytometry was used to confirm
the AA-induced cell death in MDA-MD-231 and MCF-7
Fig. 1 Cell viability was determined by MTT assays. Cells were
treated with various concentrations of AA, and results are expressed
as percentages of proliferation compared with untreated control
(mean ±SD, n=3)
Mol Biol Rep
123
cells. Indeed, both cell lines accumulated in the sub-G1
phase gradually from 24 to 72 h after treatment with AA,
whereas the number of cells in the G2/M phase decreased
in a similar fashion. These results indicate that apoptosis
was induced in MDA-MD-231 (Fig. 4a) and MCF-7 cells
(Fig. 4b).
Effects of AA on PARP cleavage and caspase-7
dependency
MDA-MB-231 and MCF-7 cells were treated with 25 and
20 lg/ml AA, respectively, and were harvested after 24, 48
Fig. 2 Typical effects of AA in reducing the viability of MCF-7
(a) and MDA-MB-231 cells (b). Cells were treated with 25 lg/mL of
AA for 24, 48 and 72 h (mean ±SD, n=3)
Fig. 3 Detection of apoptotic morphological changes in MDA-MB-
231 and MCF-7 cells treated with AA for 72 h. Nuclei were stained
with PI and examined by fluorescence microscopy. Untreated MCF-7
cells (left) and MCF-7 cells treated with 25 lg/mL AA (right);
untreated MDA-MB-231 cells (left) and MDA-MB-231 cells treated
with 20 lg/mL AA (right)
Fig. 4 MDA-MB-231 (a) and MCF-7 (b) cells were treated with 20
and 25 lg/mL AA, respectively for 24, 48 and 72 h. Cell cycle
distribution was determined in samples stained with propidium iodide
and measured by flow cytometry; percentage of cells in sub-G1, G1/S,
and G2/M phase was then calculated. Data shown are from a
representative experiment repeated three times
Mol Biol Rep
123
and 72 h of exposure. Caspase-7 cleavage was detected
after 24 h of exposure to AA, and PARP was cleaved to its
active 85 kDa form in both cell lines (Fig. 5a, b). These
results showed that AA induced apoptosis through the
cleavage of PARP, a substrate of several interleukin-1b-
converting enzyme-like proteases.
Modulation of regulatory apoptotic proteins Bad
and Bcl-2
Cell lines were treated with their respective IC
50
concen-
tration of AA, harvested after 24, 48 and 72 h of exposure,
and analyzed as described above. Pro-apoptotic Bad was
upregulated in MCF-7 cells treated for 24 h (Fig. 5c) but
anti-apoptotic Bcl-2 protein was decreased in MDA-MB-
231 cells after treatment (Fig. 5d). No changes were
observed Bcl-2 protein levels in MCF-7 cells or Bad pro-
tein levels in MBA-MB-231 cells after treatment (data not
included). The results suggest that AA-induced apoptosis
in human breast cancer cells might be mediated through the
modulation of the Bcl-2/Bad pathway.
Effects of AA on the MEK/ERK pathway
The involvement of mitogen-activated protein kinases
(MAPKs) in AA-induced apoptosis in MCF-7 and MDA-
MB-231 cells was analyzed by assessing the time-depen-
dent effect on the ERK1/2 MAPK pathway. As shown in
Fig. 6a, AA-induced inactivation of ERK1/2 began at 48 h
and lasted up to 72 h in MCF-7 cells. In contrast, phospho-
ERK1/2 was slowly downregulated by AA over 72 h in
MDA-MB-231 cells (Fig. 6b). The same blots were sub-
sequently stripped and re-blotted with an antibody that
recognized total ERK to verify equal amounts of the pro-
tein in various samples. MEK1/2 phosphorylation was
decreased in a time-dependent fashion following AA
treatment over the same timeframe, as seen for phosphor-
ylated ERK1/2 (Fig. 6c, d). Given that ERK1/2 activation
is considered to be a determining factor in cell survival and
apoptosis, these results suggest that AA-induced apoptosis
in both cell lines may be associated with activation of the
MEK/ERK pathway.
Discussion
The drug discovery process is becoming more complex and
capital-intensive, and systematic and critical review of the
methods and approach towards the entire process is
required to rediscover the discovery process afresh.
Screening of medicinal plants for potential anticancer
properties has increased greatly over the past few decades.
For instance, the US National Cancer Institute has imple-
mented a large-scale project of acquisition and screening of
compounds isolated from medicinal plants originating from
various regions of the world. These medicinal plants are
identified based on ethnopharmacological, chemosystemic
and ecological information. In the present study, irrevers-
ible inhibition of proliferation was observed in AA-treated
Fig. 5 Effects of AA on cleaved PARP and caspase-7 proteins.
MCF-7 cells were treated with 25 lg/mL AA (a) and MDA-MB-231
cells were treated with 20 lg/mL AA (b) for indicated times. Total
cell lysates were prepared and western blotting was performed with
antibodies specific for corresponding proteins. Effects of AA on Bad
protein; MCF-7 cells were treated with 25 lg/mL AA for indicated
times (c). Effects of AA on Bcl-2 protein; MDA-MB-231 cells were
treated with 20 lg/mL AA for indicated times (d)
Fig. 6 Effects of AA on the levels of ERK1/2, pERK1/2, MEK1/2
and pMEK1/2 in MCF-7 (a,c) and MDA-MD-231 (b,d) cells. Cells
were cultured as described in the ‘Materials and methods’ section.
MCF-7 and MDA-MB-231 cells were treated with 25 and 20 lg/mL
AA, respectively, for 24, 48 and 72 h. Cells were harvested and total
cell lysates were prepared. Western blotting was performed with
antibodies specific for corresponding proteins. Experiments were
repeated three times with similar results
Mol Biol Rep
123
breast cancer cells in a concentration and time-dependent
fashion. Thus, it is clear that AA inhibits cell proliferation
via apoptotic death, as visualized by nuclear fragmentation
and condensation, as well as increased sub-G1 phase.
Apoptosis is an active physiological process resulting in
cellular self-destruction that involves specific morphological
and biochemical changes in the nucleus and cytoplasm [20].
Agents that suppress the proliferation of malignant cells by
inducing apoptosis may represent a useful mechanistic
approach to both cancer chemoprevention and chemotherapy.
While many anticancer agents have been developed, unfa-
vorable side-effects and resistance are serious problems [21].
Thus, there is growing interest in the use of plant materials for
the treatment of various cancers, and for the development of
safer and more effective therapeutic agents [22]. AA has been
used as a folk remedy for several diseases without any
understanding of the underlying mechanisms. Therefore, we
chose to investigate the role of AA in the inhibition of pro-
liferation and promotion of apoptosis in human breast cancer
MDA-MB-231 and MCF-7 cells. AA treatment induced the
activation of caspase-7 in these cell lines. An inactive caspase-
7 precursor was cleaved to form the active protease during
apoptosis, resulting in PARP degradation.
In general, apoptosis is controlled by the complex inter-
play between regulatory proteins of the Bcl-2 family [23].
These pro- and anti-apoptotic proteins are key regulators of
the intrinsic apoptotic pathway, controlling the point of no
return and setting the threshold for engagement of the death
machinery [24]. Previous reports have shown that the ratio
of Bax to Bcl-2 determines, in part, the susceptibility of cells
to death signals [25]. Therefore, Bcl-2 proteins have
emerged as attractive targets for the development of novel
anticancer drugs [26]. Changes in the Bcl-2/Bax ratio have
been reported to be caused by downregulation of Bcl-2 and
slight downregulation of Bax [27], downregulation of Bcl-2
and upregulation of Bax [28,29], and downregulation of
Bcl-2 with no change in the level of Bax [30]. However,
other members of the Bcl-2 family, Bax, Bad, Bak, Bik and
Bid, promote cell death [31]. Anti-apoptotic Bcl-2 expres-
sion was significantly downregulated after AA exposure for
48 h in MDA-MB-231 cells. However, our results clearly
showed upregulation of Bad after treatment of MCF-7 for
24 h. Thus it is reasonable to conclude that AA treatment
may induce apoptosis by regulating the Bcl-2 family.
In addition, MAPK cascades transmit and amplify sig-
nals involved in cell proliferation and apoptosis. Three
major MAPK pathways exist in human tissues, but the
ERK1/2 cascade is most relevant to breast cancer because
if the appropriate receptors are present, upregulation of
ligands may be responsible for increased MAPKs in these
cancers [32]. Exposure of MDA-MB-231 and MCF-7 cells
to AA resulted in highly significant inhibition of MEK and
ERK1/2. The mechanism of action of many anticancer
drugs is based on their ability to induce apoptosis [33,34].
Hence, we were interested in identifying if cancer cells
treated with methanolic extracts of AA utilized apoptosis
as their mode of cell death. This was approached by
studying distinct morphological features (nuclear chroma-
tin condensation, fragmentation of nuclear material) and
molecular features (expression of certain crucial genes).
The MAPK pathway represents a cascade of phosphor-
ylation events including three pivotal kinases, namely Raf,
MEK and ERK; activated MEK1/2 can activate ERK1/2.
This concurs with the observation of Agarwal et al. [35]
who showed that a polyphenolic fraction isolated from
grape seeds induced growth inhibition of breast MDA-MB-
468 carcinoma cells by inhibiting MAPK activation. Taken
together, we therefore suggest that AA plays critical roles
in apoptotic and MAPK pathways. The benefit of herbal
decoctions is that they can nourish the body as a whole by
supporting various organ systems. More importantly as
they have no synthetic elements, there is very less likeli-
hood of an unexpected adverse effect.
In conclusion, AA inhibits proliferation of human breast
cancer MDA-MB-231 and MCF-7 cells through the
induction of apoptosis by regulating Bcl-2 family proteins
and MEK/MAPK signaling. We also found in this study
that p53-independent cell death induced by AA is regulated
Fig. 7 Schematic summary of our findings. On the basis of the results
of the current study, we propose that AA treatment triggers activation
of the MEK/ERK pathway, which then initiates the mitochondrial
pathway of caspase activation, and regulates Bad and Bcl-2 family
proteins, culminating in the apoptotic death of MCF-7 and MDA-MB-
231 cells
Mol Biol Rep
123
through an MEK–ERK–mitochondria–caspase cascade that
may be critical to improvement of the clinical outcome
(Fig. 7). This suggests AA extract has an anticancer effect
that is mediated via the apoptotic pathway in human breast
cancer cell lines. However, the potent extracts need to be
tested on several other cancer cell lines, and animal models
should be used to establish the therapeutic efficacy and
toxicity of this substance. In addition, extracts must be
subjected to HPLC and GC–MS analyses to identify and
characterize the efficacious phytotherapeutic and/or bio-
active compound(s) in AA.
References
1. Koul MK (1997) Medicinal Plants of Kashmir and Ladakh,
Temperate and Cold Arid Himalaya, Indus Publishing Company,
FS-5, Tagore Garden, New Delhi p 102, ISBN: 81-7837-061-6
2. Juteau F, Jerkovic I, Masotti V, Milos M, Mastelic J, Bessiere
JM, Viano J (2003) Composition and anti-microbial activity of
essential oil of Artemisia absinthium from Croatia and France.
Planta Med 69:158–161
3. Saban K, Recep M, Ahmet CAA, Ali Y (2005) Determination of
the chemical composition and antioxidant activity of the essential
oil of Artemisia dracunculus and of the antifungal and antibac-
terial activities of Turkish Artemisia absinthium,Artemisia dra-
cunculus,Artemisia santonicum, and Artemisia spicigera
essential oils. J Agric Food Chem 53:9452–9458
4. Meschler JP, Howlett AC (1999) Thujone exhibits low affinity for
cannabinoid receptors but fails to evoke cannabimimetic
responses. Pharm Biochem Behav 62:413–480
5. Baytop (1984) Therapy with Medicinal Plants in Turkey. Istanbul
University Press, Istanbul, pp 166–167
6. Jo EH, Kim SH, Ra JC, Kim SR, Cho SD, Jung JW et al (2005)
Chemopreventive properties of the ethanol extract of Chinese
licorice (Glycyrrhiza uralensis) root: induction of apoptosis and
G1 cell cycle arrest in MCF-7 human breast cancer cells. Cancer
Lett 230:239–247
7. Wu CC, Chan ML, Chen WY, Tsai CY, Chang FR, Wu YC
(2005) Pristimerin induces caspase-dependent apoptosis in MDA-
MB-231 cells via direct effects on mitochondria. Mol Cancer
Ther 4:1277–1285
8. Garcia-Carbonero R, Supko JG (2002) Current perspectives on
the clinical experience, pharmacology, and continued develop-
ment of the camptothecins. Clin Cancer Res 8:641–661
9. Rowinsky EK, Donehower RC (1995) Paclitaxel (taxol). N Engl J
Med 332:1004–1014
10. Zhu JY, Lavrik IN, Mahlknecht U, Giaisi M, Proksch P, Kram-
mer PH, Li- Weber M (2007) The traditional Chinese herbal
compound rocaglamide preferentially induces apoptosis in leu-
kemia cells by modulation of mitogen-activated protein kinase
activities. Int J Cancer 121:1839–1846
11. Huang M, Gao H, Chen Y, Zhu H, Cai Y, Zhang X, Miao Z, Jiang
H, Zhang J, Shen H, Lin L, Lu W, Ding J (2007) Chimmitecan, a
novel 9-substituted camptothecin, with improved anticancer
pharmacologic profiles in vitro and in vivo. Clin Cancer Res
13:1298–1307
12. Tamvakopoulos C, Dimas K, Sofianos ZD, Hatziantoniou S, Han
Z, Liu ZL, Wyche JH, Pantazis P (2007) Metabolism and anti-
cancer activity of the curcumin analogue, dimethoxycurcumin.
Clin Cancer Res 13:1269–1277
13. Li L, Gao Y, Zhang L, Zeng J, He D, Sun Y (2008) Silibinin
inhibits cell growth and induces apoptosis by caspase activation,
downregulating surviving and blocking EGFR-ERK activation in
renal cell carcinoma. Cancer Lett 272:61–69
14. Razis ED, Fountzilas G (2001) Paclitaxel: epirubicin in meta-
static breast cancer–a review. Ann Oncol 12:593–598
15. Hainsworth JD, Greco FA (1995) Etoposide: twenty years later.
Ann Oncol 6:325–341
16. Jordan MA, Thrower D, Wilson L (1991) Mechanism of inhibi-
tion of cell proliferation by Vinca alkaloids. Cancer Res 51:
2212–2222
17. Ganry O (2002) Phytoestrogen and breast cancer prevention. Eur
J Cancer Prev 11:519–522
18. Sun SY, Hail N, Lotan R (2004) Apoptosis as a novel target for
cancer chemoprevention. J Natl Cancer Inst 96:662–672
19. Shafi G, Munshi A, Hasan TN, Alshatwi AA, Jyothy A, Lei DKY
(2009) Induction of apoptosis in HeLa cells by chloroform frac-
tion of seed extracts of Nigella sativa. Cancer Cell Int 9:29
20. Mans DRA, Da Rocha BA (2000) Schwartsmann G. Anti-cancer
drug discovery and development in Brazil: target plant as a
rational strategy to acquire candidate anti-cancer compounds. The
Oncologist 5:185–198
21. Khan MR, Mlungwana SM (1999) c-sitosterol, a cytotoxic sterol
from Markhamia zanzibarica and Kigelia africana. Fitoterapia
70:96–97
22. Panchal RG (1998) Novel therapeutic strategies to selectively kill
cancer cells. Biochem Pharmacol 55:247–252
23. Ramos S (2007) Effects of dietary flavonoids on apoptotic
pathways related to cancer chemoprevention. J Nutr Biochem
18:427–442
24. Williams GT, Smith CA (1993) Molecular regulation of apop-
tosis: Genetic controls on cell death. Cell 74:777–779
25. Marzo I, Naval J (2008) Bcl-2 family members as molecular
targets in cancer therapy. Biochem Pharmacol 76:939–946
26. Chang J, Hsu Y, Kuo P, Kuo Y, Chiang L, Lin C (2005) Increase
of Bax/Bcl-XL ratio and arrest of cell cycle by luteolin in
immortalized human hepatoma cell line. Life Sci 76:1883–1893
27. Mohammad R, Giri A, Goustin AS (2008) Small-molecule
inhibitors of Bcl-2 family proteins as therapeutic agents in cancer.
Recent Pat Anti-cancer Drug Discov 3:20–30
28. Cha YY, Lee EO, Lee HJ, Park YD, Ko SG, Kim DH et al (2004)
Methylene chloride fraction of Scutellaria barbata induces
apoptosis in human U937 leukemia cells via the mitochondrial
signaling pathway. Clin Chim Acta 348:41–48
29. Paris C, Bertoglio J, Breard J (2007) Lysosomal and mitochon-
drial pathways in milterfosine-induced apoptosis in U937 cells.
Apoptosis 12:1257–1267
30. Han MH, Yoo YH, Choi YH (2008) Sanguinarine-induced
apoptosis in human leukemia U937 cells via Bcl-2 downregula-
tion and caspase-3 activation. Chemotherapy 54:157–165
31. Reed JC (1997) Double identity for proteins of the Bcl-2 family.
Nature 387:773–776
32. Santen RJ, Song RX, McPherson R, Kumar R, Adam L, Jeng
MH, Yue W (2002) The role of mitogen-activated protein (MAP)
kinase in breast cancer. J Steroid Biochem Mol Biol 80:239–256
33. Motomura M, Kwon KM, Suh SJ, Lee YC, Kim YK, Lee IS
(2008) Propolis induces cell cycle arrest and apoptosis in human
leukemic U937 cells through Bcl-2/Bax regulation. Environ
Toxicol Pharmacol 26:61–67
34. Sen S, D’Incalci M (1992) Biochemical events and relevance to
cancer chemotherapy. FEBS Lett 307:122–127
35. Agarwal C, Sharma Y, Zhao J, Agarwal R (2000) A polyphenolic
fraction from grape seeds causes irreversible growth inhibition of
breast carcinoma MDA-MB468 cells by inhibiting mitogen-
activated protein kinases activation and inducing G1 arrest and
differentiation. Clin Cancer Res 6:2921–2930
Mol Biol Rep
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... Cancer is a disease in which the body's cells grow uncontrollably, forming a tumor that can spread to different parts of the body [107][108][109][110][111]. The mechanism of the anticancer effect A. absinthium extract was due to the activation of the mitogen-activated protein kinase/extracellular signal-regulated kinase MEK/ERK signaling pathway, which in turn stimulates the mitochondrial pathway of caspase activation and regulates Bad and Bcl-2 family proteins, resulting in the apoptotic death of MCF-7 and MDA-MB231 human cancer cells [108]. ...
... Cancer is a disease in which the body's cells grow uncontrollably, forming a tumor that can spread to different parts of the body [107][108][109][110][111]. The mechanism of the anticancer effect A. absinthium extract was due to the activation of the mitogen-activated protein kinase/extracellular signal-regulated kinase MEK/ERK signaling pathway, which in turn stimulates the mitochondrial pathway of caspase activation and regulates Bad and Bcl-2 family proteins, resulting in the apoptotic death of MCF-7 and MDA-MB231 human cancer cells [108]. ...
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Artemisia plants are traditional and ethnopharmacologically used to treat several diseases and in addition in food, spices, and beverages. The genus is widely distributed in all continents except the Antarctica, and traditional medicine has been used as antimalarial, antioxidant, anticancer, antinociceptive, anti-inflammatory, and antiviral agents. This review is aimed at systematizing scientific data on the geographical distribution, chemical composition, and pharmacological and toxicological profiles of the Artemisia genus. Data from the literature on Artemisia plants were taken using electronic databases such as PubMed/MEDLINE, Scopus, and Web of Science. Selected papers for this updated study included data about phytochemicals, preclinical pharmacological experimental studies with molecular mechanisms included, clinical studies, and toxicological and safety data. In addition, ancient texts and books were consulted. The essential oils and phytochemicals of the Artemisia genus have reported important biological activities, among them the artemisinin, a sesquiterpene lactone, with antimalarial activity. Artemisia absinthium L. is one of the most famous Artemisia spp. due to its use in the production of the absinthe drink which is restricted in most countries because of neurotoxicity. The analyzed studies confirmed that Artemisia plants have many traditional and pharmacological applications. However, scientific data are limited to clinical and toxicological research. Therefore, further research is needed on these aspects to understand the full therapeutic potential and molecular pharmacological mechanisms of this medicinal species.
... Most of the studies are concentrated on A. absinthium, which have confirmed that A. absinthium extracts have an influence on the digestion system, due to their appetite-stimulating, antiulcer, and hepatoprotective effects, among others activities [13,19,[180][181][182][183][184]. Additionally, they have also shown, inter alia, cytotoxic, anthelmintic, antiprotozoal, analgesic, immunostimulating, cytotoxic, neuroprotective, and antidepressant activities [14][15][16][17][18]25,26,[30][31][32][33][34][35][36][37]86,122,130,[185][186][187][188][189][190][191]. ...
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Artemisia species play a vital role in traditional and contemporary medicine. Among them, Artemisia abrotanum, Artemisia absinthium, Artemisia annua, Artemisia dracunculus, and Artemisia vulgaris are the most popular. The chemical composition and bioactivity of these species have been extensively studied. Studies on these species have confirmed their traditional applications and documented new pharmacological directions and their valuable and potential applications in cosmetology. Artemisia ssp. primarily contain sesquiterpenoid lactones, coumarins, flavonoids, and phenolic acids. Essential oils obtained from these species are of great biological importance. Extracts from Artemisia ssp. have been scientifically proven to exhibit, among others, hepatoprotective, neuroprotective, antidepressant, cytotoxic, and digestion-stimulating activities. In addition, their application in cosmetic products is currently the subject of several studies. Essential oils or extracts from different parts of Artemisia ssp. have been characterized by antibacterial, antifungal, and antioxidant activities. Products with Artemisia extracts, essential oils, or individual compounds can be used on skin, hair, and nails. Artemisia products are also used as ingredients in skincare cosmetics, such as creams, shampoos, essences, serums, masks, lotions, and tonics. This review focuses especially on elucidating the importance of the most popular/important species of the Artemisia genus in the cosmetic industry.
... ract significantly (p ≤ 0.05) inhibited the growth of A549 cancer cells with an IC 50 of 36.8 µg/mL for 24 h, indicating a promising anti-lung cancer activity of methanolic extract of A. absinthium leaf extract. As can be seen in(Fig.4)MTT assay showed that methanolic extract could inhibit the growth of A549 cancer cells in a dose-dependent manner.Shafi et al. (2012) observed that A. absinthium had considerable cytotoxic activities against MDA-MB-231 and MCF-7 cells with IC 50 values of 25 μg/mL and 20 μg/mL, respectively. Further, they reported that it induced apoptosis in both cells.Our results support earlier findings byGordanian et al., 2014, who found that extracts of A. absinthium and A. vulga ...
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Herbal medicines are an important and growing part of International pharmacopeia. Research and testing enhance our understanding of their medical properties, making them a safer alternative or preferable option to allopathic medication. Plant-derived pharmaceuticals are gaining popularity due to the belief that "green medicine" is safer and more trustworthy than expensive synthetic drugs. This study aimed to evaluate the antimicrobial and anticancer potential of the methanolic leaf extract of Artemisia absinthium against human lung cancer A549 cell line by well diffusion method and MTT assay, respectively. The A. absinthium leaf extract showed the highest activity against Enterococcus faecalis (20 ± 0.7 mm), and Escherichia coli (18 ± 0.8 mm), followed by Pseudomonas aeruginosa (16 ± 0.6 mm), Candida albicans (14 ± 0.9 mm) and Staphylococcus aureus (13 ± 0.8 mm), with MIC values 128, 128, 128, 256 and 256 µg/mL respectively. The methanolic extract of A. absinthium showed significant (p ≤ 0.05) cytotoxicity against the A549 cancer cell line with an IC50 value of 36.8 µg/mL. The present study's findings give strong evidence for using the methanolic leaf extract of A. absinthium as an effective ethnomedicinal agent and a possible candidate for treating various human diseases and a potent bioactive agent in anticancer medications.
... Then, by connecting to the apoptozomed complex, the apoptosomal and caspase protein (Caspase 9), and this complex also activates the Caspase of the performer (Caspase 3), which is driven by the activity of this cell caspase to death. Therefore, according to the results and studies on cancer cells, lipid nanoparticles containing Artemisia Absinthium L essential oils are probably prevented by inducing apoptosis from the continuation of cell division (22)(23)(24). ...
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Background & Objective: According to research, breast cancer is the second most common cancer among women. Nanomaterials of various materials significantly increase the solubility, stability and effective drug delivery, and in recent years research on the effectiveness of essential oils and plant extracts in inhibiting the growth of cancer cells is expanding. Artemisia belongs to the Asteraceae family. In many studies, the effectiveness of the essential oil and extract of this plant in inhibiting the growth of cancer cells has been reported. Materials & Methods: In this experiment, nanoparticles containing Artemisia absinthium L essential oil (thistle) were first synthesized by homogenizer & sonication method and then their physicochemical properties were determined, such as particle size, particle size distribution, zeta potential, percentage of loading efficiency. Then, the anti-apoptotic effect of lipid nanoparticles containing Artemisia essential oil in breast cancer cells (BRC-03) was evaluated. Results: The results of cellular effect of lipid nanoparticles containing essential oil of Artemisia absinthium L (thistle) on breast cancer cells showed that increasing the concentration of lipid nanoparticles containing essential oil of this plant reduced the survival rate of cancer cells. Breast (BRC-03) was purified compared to essential oil (p <0.05). Conclusion: Nano-essential oil of this plant is effective in reducing the IC50 of the drug and in increasing the cytotoxicity of the essential oil of the plant. Lipid nanoparticles containing essential oil of Artemisia absinthium L (thistle) activated the apoptotic pathway in breast cancer cells.
... Artemisia absinthium (AA) is an indigenous medicine locally known as "Tethwen" from the Kashmir Valley, India. Chemical analysis of the extracts of AA has detected it to be rich in antihelmintic oil known as thujone [1]. The active compounds include artemisinin and artemisinic acid and both are mainly used as antimalarial agents. ...
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Artemisia absinthium (AA) is an indigenous medicine used for treatment of inflammation of the liver and chronic fever, and is studied as an antimalarial and anticancer agent. The focus of the current investigation was to determine the action and effect of AA on microRNAs (miRNAs) from breast cancer cell lines. Molecular docking is a structure-based drug design process that studies the interaction of small molecule ligands with receptor biomacromolecules to predict binding mechanism and affinity. MiRNA expression profiling was done using microarray technology. Validation of transcripts with regulated expression pattern was done by SYBR-based quantitative real time PCR (qRT-PCR). AutoDock 4.2 programming allots polar hydrogens, bound together total Kollman charges, solvation borders, and fragmental volumes to the protein using auto dock devices in docking research (ADT). As confirmed by SYBR-based RT-PCR, our investigation discovered an upregulation of the miRNA-22 articulation and a downregulation of miRNA-199a*. These findings support and demonstrate the role of AA as a miRNA articulation-influencing factor in human breast cancer progression. AA’s tetramethoxy hydroxyflavone (p7F) molecule was found to be effective in the treatment of cancer. Changes in miRNA expression patterns could be a key pathogenic component in AA’s physiological action on cancer cells.
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Artemisia giraldii Pamp. is an herbaceous plant distributed only in some areas in China. To understand the evolutionary relationship between plastid and mitochondria in A. giraldii , we sequenced and analysed the plastome and mitogenome of A. giraldii on the basis of Illumina and Nanopore DNA sequencing data. The mitogenome was 194,298 bp long, and the plastome was 151,072 bp long. The mitogenome encoded 56 genes, and the overall GC content was 45.66%. Phylogenetic analysis of the two organelle genomes revealed that A. giraldii is located in the same branching position. We found 13 pairs of homologous sequences between the plastome and mitogenome, and only one of them might have transferred from the plastid to the mitochondria. Gene selection pressure analysis in the mitogenome showed that ccm Fc, nad 1, nad 6, atp 9, atp 1 and rps 12 may undergo positive selection. According to the 18 available plastome sequences, we found 17 variant sites in two hypervariable regions that can be used in completely distinguishing 18 Artemisia species. The most interesting discovery was that the mitogenome of A. giraldii was only 43,226 bp larger than the plastome. To the best of our knowledge, this study represented one of the smallest differences between all sequenced mitogenomes and plastomes from vascular plants. The above results can provide a reference for future taxonomic and molecular evolution studies of Asteraceae species.
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Introduction : Although the use of medicinal plants is quite frequent in Morocco, no ethnobotanical study has targeted cancer patients in the Beni Mellal-Khenifra region. We aim to measure the frequency of use of medicinal plants by these patients in the Beni Mellal-Khenifra region and to inventory those used. Methods : An ethnobotanical survey was conducted with 530 cancer patients at the regional oncology center of Beni Mellal. We conducted a semi-structured interview using a questionnaire. Prevalence of use, the relative frequency of citation (RFC), fidelity level (FL), and Informant Consensus Factor (ICF) were calculated. Results : The prevalence of herbal use was 36.6%. The plant's relative frequency of citation ranged from 0.002 to 0.15. Fifty-four species belonging to 33 different botanical families were considered. The most common plants in use were: Marrubium vulgare L. (15%), Retama monosperma (L.) Boiss (11%), and Juniperus oxycedrus L. (10%). Six plants had an FL of 100% for breast cancer treatment, and the highest ICF for liver cancer treatment was 0.50. Conclusion : More than one-third of cancer patients in the region used herbal preparations. Indeed, informants did not agree on a particular type of cancer treatment. Further research is needed to assess the biological and toxicological aspects of Retama monosperma (L.) Boiss. And Juniperus oxycedrus L.
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Background and Objective: Synthetic dyes are commonly used as food additives because of their colouring properties uniformity, stability, and little cost. However, a lot of them become toxic after prolonged use, causing health problems and induced DNA damage and chromosomal anomalies in mammalian cells. Aphthitalite and Halite are components of synthetic dyes called Artificial Tamar Hindi are used as a famous beverage in Egypt. This is the first study on Aphthitalite and Halite. The objective of this research was to evaluate the side effects of Aphthitalite and Halite (AH) as one of the famous synthetic dye are using in Egypt and reduce the side effects by using some natural material. Material and Methods: We used Vicia faba as a biological system to study the genotoxicity of AH. Green onion leaves, Boswellia carterii, and Artemisia spp were the natural material used to avoid the chromosomal aberration induced by AH. Results: The results refer that AH (which isdistinct as Aphthitalite and Halite by X-ray diffractions) reduces the rate of divisions and increases chromosomal anomalies such as laggard chromosome, micronuclei, double nuclei, bridge, and breaks. Onion leaves, Boswellia serrata and Artemisia reduce the side effects of AHconcerning MI. All-natural materials reduce the chromosomal aberration induction by AH especially the onion leaves which significantly reduce the chromosomal aberrations followed by Boswellia serrata. About the shoot and root length, AH significantly increases in root length while in shoot length there are no significant differences compared with control. Conclusion: the results indicated that natural materials reduce side effects induction by AH.
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The worldwide industry of seaweeds utilizes 7.5 to 8.0 million tons of wet seaweeds annually that are cultivated in farms, and urgent needs are growing to minimize the overexploitation of the natural populations. In vitro plant tissue culture could be one of the fashionable possible techniques. The main advantage of tissue culture is not only to overcome the excessive use of seaweeds but also to select germplasm with popular traits. Here, we present a novel explants surface sterilization method for endangered species Sargassum fusiforme using Artemisia dracunculus extract as an initial step in the tissue culture technique. Besides, a novel occurrence of identified compounds in the crude extract of A. dracunculus through UPLC-QTOF MS analysis. A crude extract of A. dracunculus herbal plant was tested for sterilizing S. fusiforme explants (leaf, stipe, and stolon) in vitro against 70% ethanol and other chemical sterilants such as povidone-iodine (PI), germanium oxide (GeO2), and antibiotics (Kanamycin, Nystatin, and Streptomycin). The crude extract of A. dracunculus showed a high microbial sterilization effect with leaves (90%) and stipes (80%) compared to stolons which gave only (20%). This study presents a novel investigation of in vitro sterilization properties of A. dracunculus as a natural and medicinal plant against contaminating microbes. We conclude the great advantage of sterilization using Artemisia extract which might probably be the most suitable protocol for sterilization compared to chemical sterilants as they have detrimental effects due to their toxicity to plant tissues.
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Throughout medical history, plant products have been shown to be valuable sources of novel anti-cancer drugs. Examples are the Vinca alkaloids, the taxanes, and the camptothecins, derived from the Madagscan periwin-kle plant Catharantus roseus, the Pacific yew Taxus brevi-folia, and the Chinese tree Camptotheca acuminata, respectively. For this reason, the South-American Office for Anti-Cancer Drug Development has implemented a large-scale project of acquisition and testing of compounds isolated from South American medicinal plants. The species are selected on the basis of a potentially useful phytochemical composition by consulting ethnopharma-cological, chemosystemic, and ecological information. The collected samples are dried and first extracted with an organic solvent, then with distilled water. These crude extracts are evaluated at a concentration of 50 µg/ml for antiproliferative activity against one cell line. Extracts that significantly inhibit the growth of the cells (≥50%) at relatively low concentrations (≤50 µg/ml) are submitted to the more comprehensive disease-oriented screen of the U.S. National Cancer Institute. In parallel, these samples are further purified by bioassay-guided purification, involving repeated fractionation by diverse chromatography methods. If the active substance is expected to represent a novel structure, it is identified by appropriate chemical techniques, mechanistic studies are performed with a wide diversity of tumor models and laboratory techniques, and efforts are undertaken for the synthesis of potentially more useful analogs.
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We investigated mechanism(s) where propolis induces apoptosis in human leukemic U937 cells. Propolis inhibited the proliferation of U937 cells in a dose-dependent manner by inducing apoptosis and blocking cell cycle progression in the G2/M phase. Western blot analysis showed that propolis increases the expression of p21 and p27 proteins, and decreases the levels of cyclin B1, cyclin A, Cdk2 and Cdc2, thereby contributing to cell cycle arrest. DAPI staining assay revealed typical morphology features of apoptotic cells. Propolis-induced apoptosis was also confirmed by assays with annexin V-FITC, PI-labeling and DNA fragmentation assay. The increase in apoptosis level induced by propolis was associated with down-regulation of Bcl-2 and activation of caspase-3, but not with Bax. These results suggests that propolis-induced apoptosis is related to the selective activation of caspase-3 and induction of Bcl-2/Bax regulation.
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