Novel dammarane-type saponins from Gynostemma pentaphyllum and their neuroprotective effect

Article abstract of DOI:10.1080/14786419.2018.1495638

Three novel dammarane-type saponins, 2α,3β,12β,20(S),24(S)-pentahydroxydammar-25-ene-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-20-O-β-D-glucopyranoside (1, namely gypenoside J1), 2α,3β,12β,20(S),25-pentahydroxydammar-23-ene-3-O-β-D-glucopyranosyl-(1

Full text of DOI:10.1080/14786419.2018.1495638

Natural Product Research
Formerly Natural Product Letters
ISSN: 1478-6419 (Print) 1478-6427 (Online) Journal homepage: http://www.tandfonline.com/loi/gnpl20
Novel dammarane-type saponins from
Gynostemma pentaphyllum and their
neuroprotective effect
Shao-Fang Xing, Man Lin, Yu-Rong Wang, Tuo Chang, Wei-Ye Cui & Xiang-Lan
Piao
To cite this article: Shao-Fang Xing, Man Lin, Yu-Rong Wang, Tuo Chang, Wei-Ye Cui & Xiang-
Lan Piao (2018): Novel dammarane-type saponins from Gynostemmaꢀpentaphyllum and their
neuroprotective effect, Natural Product Research
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NATURAL PRODUCT RESEARCH
https://doi.org/10.1080/14786419.2018.1495638
Novel dammarane-type saponins from Gynostemma
pentaphyllum and their neuroprotective effect
a,b
a,b
a,b
a,b
Shao-Fang Xing , Man Lin , Yu-Rong Wang , Tuo Chang ,
a,b
a,b
Wei-Ye Cui and Xiang-Lan Piao
a
b
School of Pharmacy, Minzu University of China, Beijing, P.R. China; Key Laboratory of
Ethnomedicine (MINZU University of China), Ministry of Education, Beijing P.R. China
ABSTRACT
ARTICLE HISTORY
Three novel dammarane-type saponins, 2a,3b,12b,20(S),24(S)-
pentahydroxydammar-25-ene-3-O-b-D-glucopyranosyl-(1!2)-b-D-
glucopyranosyl-20-O-b-D-glucopyranoside (1, namely gypenoside
J1), 2a,3b,12b,20(S),25-pentahydroxydammar-23-ene-3-O-b-D-glu-
copyranosyl-(1!2)-b-D-glucopyranosyl-20-O-b-D-glucopyranoside
Received 4 April 2018
Accepted 26 June 2018
KEYWORDS
Gynostemma pentaphyllum;
dammarane-type saponin;
gypenoside; neuroprotective
effect; SH-SY5Y
(
2, namely gypenoside J2) and 2a,3b,12b,20(S)-tetrahydroxydam-
mar-25-en-24-one-3-O-b-D-glucopyranosyl-(1!2)-b-D-glucopyrano-
syl-20-O-b-D-xylopyranosyl-(1!6)-b-D-glucopyranoside (3, namely
gypenoside J3) along with one known gypenoside (gypenoside
LVII) were isolated from the aerial parts of G. pentaphyllum using
various chromatographic methods. Their structures were eluci-
1
13
dated on the basis of IR, 1D- ( H and C), 2D-NMR spectroscopy
HSQC, HMBC and COSY), and mass spectrometry (ESI-MS/MS).
(
Their activity was tested using CCK-8 assay. These four com-
pounds showed little anti-cancer activity with IC50 values more
than 100 lM against four types of human cancer lines. The
effects of them against H O -induced oxidative stress in human
2 2
neuroblastoma SH-SY5Y cells were evaluated and they all
showed potential neuroprotective effects with 3.64–18.16%
2 2
higher cell viability than the H O -induced model group.
1. Introduction
Gynostemma pentaphyllum (Thunb.) Makino, which belongs to the family
Cucurbitaceae, is a perennial creeping plant commonly grown in China, Japan, India
and Korea. In China, G. pentaphyllum is also called ‘Jiaogulan’ (Wang et al. 2017; Shi
CONTACT Xiang-Lan Piao
xlpiao@163.com; xlpiao@muc.edu.cn
Supplemental data for this article can be accessed at https://doi.org/10.1080/14786419.2018.1495638.
ß 2018 Informa UK Limited, trading as Taylor & Francis Group

2
S.-F. XING ET AL.
et al. 2018) and mainly grows in Zhangzhou, Fujian Province, Jinxiu, Guangxi Province,
Pingli, Shaanxi Province and Enshi, Hubei Province and has been income resource for
local farmers. Gypenosides, dammarane-type saponins, have been found as main con-
stituents in Gynostemma and all possess numerous bioactivities, such as antilipidermic
(Huang et al. 2005), anti-inflammatory (Xie et al. 2010), cardiovascular (Circosta et al.
2005), antioxidant and hepatoprotective (Lin et al. 2000) effects. Gypenosides have
similar structures to ginsenosides. However, gypenosides can be more easily isolated
from G. pentaphyllum than ginsenosides from P. ginseng (Ky et al. 2010). In addition,
G. pentaphyllum is more easily obtained than medicinal P. ginseng, whose cultivation is
highly specialized, requiring a maturation period of up to 5–6 years. Due to this
reason, G. pentaphyllum has increasingly attracted the interest of continuous research.
Gypenosides with strong anti-tumor activity have been isolated from G. pentaphyl-
lum from Zhangzhou, Fujian Province, China, in our previous research (Piao et al. 2013;
Xing et al. 2016). In this study, we reported isolation, structural elucidation and
bioactivity evaluation of gypenosides from G. pentaphyllum.
2. Results and discussion
Structure elucidation of all isolated compounds was achieved mainly by extensive
1
13
1
D-( H and C), 2D-NMR spectroscopy (HSQC, HMBC and COSY), mass spectrometry
(ESI-MS/MS) and comparison of spectroscopic data with literature values.
Compound 1 was obtained as a white amorphous powder. Its molecular formula
ꢀ
was deduced as C H O based on the HRESIMS at m/z 977.5295 [M-H] (calcd for
4
8 82 20
C H O , 977.5321, Error: 2.17). MS/MS analysis of compound 1 (negative ion mode),
4
8 81 20
ꢀ
ꢀ
showed the fragment ions at m/z 815.4732 [M-H-162] , 653.4212 [M-H-162-162] ,
91.3711 [M-H-162-162-162] , which indicated that there were three hexose units.
ꢀ
4
Acidic hydrolysis and R values in thin layer chromatography (TLC) indicated all hexose
f
units were D-glucose (Figure S33). The IR spectrum showed the presence of hydroxyl
ꢀ
1
ꢀ1
(
3416 cm ), olefinic C=C double bonds (1632 cm ) and glycosidic linkage (1075
ꢀ
1
1
cm ) groups. The H NMR spectrum (Table S1) exhibited signals for seven methyl
groups at d 1.72, 1.31, 1.13, 1.02, 0.99, 0.93, 0.92, which correlated in HSQC spectrum
H
with six carbon signals at d 16.6, 21.5, 27.3, 14.8, 16.4, 15.8, 16.4, respectively and
C
13
two olefinic protons at d 4.81 (1H, s) and 4.94 (1H, s). The C NMR data including
H
DEPT and HSQC spectra of 1 showed 48 carbon resonances comprising 6 quaternary
carbons, 23 methines, 12 methylenes, and 7 methyls, of which 30 were assigned to
the aglycone and 18 to the sugar moieties (Table S2). Analysis of the 1D NMR and 2D
NMR spectrum data of 1 showed signals assignable to a b-D-glucopyranosyl-(1!2)-
0
00
b-D-glucopyranosyl moiety [d 4.46 (d, J = 7.7 Hz, H-1 ) and d 4.76 (d, J = 7.7 Hz, H-1 )]
0
00
and a b-D-glucopyranosyl moiety [d 4.58 (d, J = 7.8 Hz, H-1 )]. The b-glycosidic link-
ages were evident from the J values in the H NMR spectrum (J1
1
0
0
= 7.7 Hz, J 00 00 = 7.7
2 1 2
Hz, J1000 000 = 7.8 Hz). The chemical shifts of the sugars were assigned by analysis of
2
COSY and HMBC data, as shown in Figure S1. The locations of the monosaccharide
and disaccharide were determined as at the C-20 and C-3 positions by the observed
000
HMBC correlations between H-1 (dH 4.58) and C-20 (d 83.5) and between H-1' (dH
C
4
.46) and C-3 (dC 95.3), between H-1'' (dH 4.76) and C-2' (dC 79.3), respectively.

NATURAL PRODUCT RESEARCH
3
Figure 1. Chemical structures of gypenoside J1 (1), gypenoside J2 (2), gypenoside J3 (3), gypeno-
side LVII (4).
Furthermore, the side-chain of the aglycone moiety was also identified by analysis of
the HMBC data (Table S2 and in Figure S1), which showed correlations between pro-
tons and carbons: H-27 and C-24, C-25, C-26, H-26 and C-27. Thus, compound 1 was
identified as 2a,3b,12b, 20(S),24(S)-pentahydroxydammar-25-ene-3-O-b-D-glucopyrano-
syl-(1!2)-b-D-glucopyranosyl-20-O-b-D- glucopyranoside, and named as gypenoside
J1 (Figure 1) for convenience.
Compound 2 was isolated as a white amorphous powder. From the HRESIMS at m/
ꢀ
z 977.5293 [M-H] (calcd for C H O , 977.5321, Error: 1.96), its molecular formula
4
8 81 20
was determined as C H O , which was equal to that of compound 1. The ESI-MS/
4
8 82 20
ꢀ
MS showed a prominent fragment ions peak at m/z 815.4735 [M-H-162] , 653.4212
M-H-162-162] , 491.3694 [M-H-162-162-162] , due to the loss of three hexose units.
ꢀ
ꢀ
[
Acidic hydrolysis and R values in TLC indicated all hexose units were D-glucose
f
(
Figure S33). Its IR spectrum was similar to that of 1, suggesting that compound 2
ꢀ
1
ꢀ1
also possesses hydroxyl (3412 cm ), olefinic C = C double bonds (1635 cm ) and
glycosidic linkage (1076 cm ). The H NMR signals of the aglycone of 2 (Table S1)
ꢀ
1
1
showed signals assignable to eight methyl singlets at dH 1.35, 1.30, 1.30, 1.16, 1.07,
1.03, 0.96, 0.96, which correlated in the HSQC spectrum with eight carbon signals at
dC 22.2, 28.8, 28.5, 27.3, 14.9, 16.4, 15.7, 16.4, respectively (Table S2) and two olefinic
protons at d 5.74 (1H, m) and 5.74 (1H, m). The carbon signals of the saccharide moi-
H
13
eties and the aglycone moiety in the C NMR spectrum of 2 (Table S2) were almost
superimposable with those of gypenoside J1, except for the resonances due to the

4
S.-F. XING ET AL.
side-chain from C-22 to C-27 position. The HMBC spectrum (Figure S1) of compound 2
showed correlations between the following protons and carbons: H-22 and C-23, H-23
and C-22, -25; H-24 and C-22, -25; H-26 and C-24, -25; H-27 and C-24, 25, 26, respect-
ively. Thus, compound 2 was established as 2a,3b,12b,20(S),25-pentahydroxydammar-
2
3-ene-3-O-b-D-glucopyranosyl-(1!2)-b-D-glucopyranosyl-20-O-b-D-glucopyranoside,
which was named gypenoside J2 (Figure 1).
Compound 3 was isolated as an amorphous powder. The molecular formula of
ꢀ
C H O was assigned from the HRESIMS data (m/z 1107.5613 [M-H] , calcd for
5
3 88 24
C H O , 1107.5587, Error: 2.32). The ESI-MS/MS showed prominent fragment ions
5
3 87 24
ꢀ
ꢀ
peak at m/z 945.4987 [M-H-162] , 813.4570 [M-H-162-132] , 651.4048 [M-H-162-132-
62] , 489.3540 [M-H-162-132-162-162] , which indicated three hexose units and one
ꢀ
ꢀ
1
pentose unit. Acidic hydrolysis and R values in TLC indicated all hexose units were
f
D-glucose and one pentose unit was D-xylose (Figure S33). The IR spectrum showed the
ꢀ
1
ꢀ1
presence of hydroxy (3422 cm ), olefinic C = C double bonds (1635 cm ) and glycosidic
ꢀ
1
linkage (1077 cm ). The disaccharide in C-20 position was identified as one b-D-xylopyra-
nosyl-(1!6)-b-D-glucopyranosyl moiety [d 4.60 (d, J = 7.8 Hz, H-1 ) and d 4.28 (d, J = 7.5
0
00
0
000
Hz, H-1 )], which were parallel to those of gypenoside LVI (Chen et al. 2014). On the basis
of the above spectroscopic data, compound 3 was elucidated as 2a,3b,12b,20(S)-tetrahy-
droxydammar-25-en-24-one-3-O-b-D-glucopyranosyl-(1!2)-b-D-glucopyranosyl-20-O-
b-D-xylopyranosyl-(1!6)-b-D-glucopyranoside, named gypenoside J3 (Figure 1).
The known dammarane-type saponin was an amorphous powder and identified by
comparison of its reported spectroscopic data as gypenoside LVII (Takemoto and
Arihara 1986) (Figure 1).
All isolates were firstly evaluated for their anti-cancer effects. All isolates showed
weak cytotoxicity with the half inhibitory concentration (IC ) values more than 100
50
lM. It might be the sugar number or the side-chain structure that influenced the anti-
tumor activity referring to our previous report (Chen, et al. 2014).
There were lots of reports about ginsenoside Rb1, which was a similar dammarane-
type saponins with four sugar moieties, as a neuroprotective agent (Ahmed et al.
2016). Based on this, the neuroprotective effects of all isolates were investigated. The
isolates did not exert cytotoxic effects on the SH-SY5Y cells at 5, 10, 20, 40 lM when
incubated for 48 h as cell viability (all >95%) was almost not affected. The cell viability
of SH-SY5Y cells was suppressed at 67.27% by H O (850 lM). Compared to positive
2
2
control vitamin C, all isolates has considerable protective effect with 3.64–18.16%
higher cell viability than the H O -induced model group (Figure S2). In addition, all
2
2
compounds displayed a dose-dependent neuroprotective manner.
Oxidative stress is a major component of the harmful cascades activated in the
development of aging-related neurodegenerative disorders, such as Alzheimer’s
disease (AD) and Parkison’s disease (Tabner et al. 2005). Overproduction of reactive
oxygen species (ROS) causes cell damage through the promotion of lipid peroxidation,
DNA damage, and the regulation of death proteins (Uttara et al. 2009). Thus, anti-
oxidant therapy is considered as a promising approach in prevention and clinical
management of AD. There is increasing evidence showing that naturally occurring
antioxidants from fruits and vegetables can protect the human body from ROS effects
(Yonny et al. 2016). Therefore, the development and utilization of more effective

NATURAL PRODUCT RESEARCH
5
antioxidants from natural products is highly desired. G. pentaphyllum is a medical and
edible plant and has been used for centuries. In the present study, we isolated
gypenosides from G. pentaphyllum with neuroprotective effect against the in vitro
model of human neuronal SH-SY5Y cells, indicating that G. pentaphyllum could use
as neuroprotective plant resource.
3
. Experimental
.1. General experimental procedures
Separation and purification were successively performed by ion exchange resin HP20
MITSUBISHI CHEMICAL, Japan), silica gel in 200–300 mesh (Qingdao Marine chemical,
3
(
China) column chromatography, one rapid purification preparative liquid chromato-
graphy system with Flash Chromatography Cartridges SNAP KP-Sil 340 g (Biotage,
Sweden) and a Shimadzu semi-preparative HPLC system (Kyoto, Japan) with LC-20AT
pumps and a SPD-M20A detector using a RP C18 column (250 mm ꢁ10 mm, 5 lm). IR
data were detected on a VERTEX 70 Fourier Transform Infrared Spectrometer (Bruker,
Germany), 1D- and 2D-NMR spectra were recorded in CD OD on a Bruker AVANCE 600
3
1
NMR spectrometer (Bruker, Switzerland, 600 MHz for H NMR), and HRESIMS spectra
were obtained from a LCMS-IT-TOF spectrometer (Shimadzu, Japan), the negative
electrospray ionisation (ESI) mode with -3.5 kV spray voltage was used and the ion
scanning range was m/z 200–1200.
3.2. Plant material
The air-dried aerial parts of G. pentaphyllum were purchased at Zhangzhou, Fujian
Province, China, in November 2016 and have been identified professionally. Voucher
specimen (No. GP2016-01) was deposited at the Isolation and Structure Identification
Laboratory in Minzu University of China, China.
3.3. Extraction and isolation
The air-dried aerial parts of G. pentaphyllum (5 kg) were extracted with 80% ethanol
for 3 h three times. The organic solvent was removed under a vaccum to give 0.9 kg
of ethanol extract. The ethanol extract was suspended with proper water and then
separated by resin HP20 in succession with 20, 50, 70 and 95% ethanol. The 70%
ethanol fraction (450 g) was chromatographed over a silica gel column (120 ꢁ 1300
mm). Elution with a CH Cl -MeOH gradient (10:1-1:1) yielded ten fractions GP70A-J.
2
2
Fraction GP70H (144 g) was subjected to rapid purification preparative liquid chroma-
tography system for 9 times and eluted with gradient solvent system of 40–95%
methanol in water for 12 column volumes at flow of 50 ml/min and detection at 203
nm. 56–57% eluent was collected to yield fraction GP70H56-57 (5.3 g). Compounds 1
(
6.3 mg) at retention time t (min) 17.9, 2 (7.2 mg) at t (min) 18.8 and 3 (6.4 mg) at
R R
t (min) 21.8, were purified from GP70H56-57 by semi-preparative HPLC using CH CN/
R
3
H O (27%, v/v). Compound 4 (200 mg) at t (min) 18.1 was purified from GP70B (18.5
2
R
g) by semi-preparative HPLC using CH CN/H O (40%, v/v).
3
2

6
S.-F. XING ET AL.
3.4. Spectroscopic data of compounds 1–3
25
Gypenoside J1 (1): white, amorphous powder; [a] : þ10 (c 0.1, MeOH); IR (KBr):
D
ꢀ
1
ꢀ
mmax 3416, 2925, 1632, 1384, 1075, 899 cm ; HRESIMS m/z 977.5295 [M-H] (calcd for
ꢀ
ꢀ
C H O , 977.5321, Error: 2.17), 815.4732 [M-H-162] , 797.4631 [M-H-162-18] ,
53.4212 [M-H-162-162] , 635.4102 [M-H-162-162-18] , 491.3711 [M-H-162-162-162] ;
H and C NMR (MeOH-d , 600 and 150 MHz), see Table S1 and S2.
4
8 81 20
ꢀ
ꢀ
ꢀ
6
1
13
4
25
Gypenoside J2 (2): white, amorphous powder; [a] : þ10 (c 0.1, MeOH); IR (KBr):
D
ꢀ
1
ꢀ
mmax 3412, 2941, 1635, 1384, 1076, 893 cm ; HRESIMS m/z 977.5293 [M-H] (calcd for
ꢀ
ꢀ
C H O , 977.5321, Error: 1.96), 815.4735 [M-H-162] , 797.4628 [M-H-162-18] ,
53.4212 [M-H-162-162] , 635.4106 [M-H-162-162-18] , 491.3694 [M-H-162-162-162] ;
H and C NMR (MeOH-d , 600 and 150 MHz), see Table S1 and S2.
Gypenoside J3 (3): white, amorphous powder; [a] : -10 (c 0.1, MeOH); IR (KBr):
mmax 3422, 2922, 1632, 1384, 1077, 1042, 815 cm ; HRESIMS m/z 1107.5596 [M-H]
calcd for C H O , 1107.5587, Error: 2.32), 945.4987 [M-H-162] , 813.4570 [M-H-162-
32] , 795.4467 [M-H-162-132-18] , 651.4048 [M-H-162-132-162] , 633.3940 [M-H-162-
32-162-18] , 489.3540 [M-H-162-132-162-162] ; H and C NMR (MeOH-d , 600 and
4
8 81 20
ꢀ
ꢀ
ꢀ
6
1
13
4
25
D
ꢀ
1
ꢀ
ꢀ
ꢀ
(
5
3 87 24
ꢀ
ꢀ
1
1
1
ꢀ
ꢀ
1
13
4
50 MHz), see Table S1 and S2.
3.5. Acidic hydrolysis of compounds 1–3 and determination of
sugar components
ꢂ
Compounds 1–3 (each 4.0 mg) were dissolved in 1 M HCl (1 ml) and heated at 80 C
for 6 h in a water bath. Thin layer chromatography (TLC) assay was used for sugar
identification with silica gel 60 F254 glass plates (Merk, Germany). The developing
solvent was chloroform: methanol: formic acid (500:150:1). 12% sulphuric acid in etha-
nol was used as carbonation solution. The standard sugars gave R values as follows:
f
0.66 for L-arabinose, 0.73 for D-xylose, 0.46 for D-glucose, 0.41 for D-galactose, 0.49 for
D-mannose. Compound 1 and 2 gave R value 0.46 for D-glucose and compound 3
f
gave R values 0.73 for D-xylose and 0.46 for D-glucose.
f
3.6. Cell culture
Four types of human cancer cells (lung cancer cell line A549, liver cancer line HepG2,
stomach cancer cell line SGC7901 and prostate cancer cell line PC-3) and human
neuroblastoma cell line SH-SY5Y were obtained from China Infrastructure of Cell Line
Resources (Beijing, China). HepG2 cells and SH-SY5Y cells were cultured in DMEM,
A549 cells and SGC7901 cells were cultured in RPMI 1640 media and PC-3 cells
were cultured in F12K media. All media were supplemented with 10% FBS and 1%
ꢂ
penicillin-streptomycin at 37 C in a humid atmosphere with 5% CO .
2
3.7. Cytotoxicity assay
Stocks of the isolates were prepared at a concentration of 1mg/ml. Human lung
cancer A549 cells, liver cancer HepG2 cells, stomach cancer SGC 7901 cells and pros-
tate cancer PC-3 cells were used to evaluate the anti-cancer activity and the cytotoxic

NATURAL PRODUCT RESEARCH
7
effects were performed by a Cell-Counting Kit (CCK-8, Dojindo, Japan) assay. In brief,
3
cancer cells (5 ꢁ 10 cells/well) were treated with specified concentrations of com-
ꢂ
pounds (6.25, 12.5, 25, 50 and 100 lM). After incubated at 37 C for 24 h, the medium
was removed. One hundred microliters of 10% CCK-8 solution was added to each well.
ꢂ
After incubation for 3 h at 37 C, the absorbance of each well was then measured
at 450 nm using a Benchmark Plus microplate spectrophotometer (Bio-Rad, Japan).
IC50 (concentration in mM required to inhibit cancer cells by 50%) was used to
determine the inhibition.
3.8. Neuroprotection evaluation assay
H O -induced cytotoxicity in neuroblastoma cell line SH-SY5Y was regarded as a
2
2
cultured cell model of oxidative damage to evaluate neuroprotection. Briefly, SH-SY5Y
3
cells (5 ꢁ 10 cells/well) were seeded in 96-well plates and were incubated for 1 d to
allow for attachment. H O was used to induce oxidative stress. SH-SY5Y cells were
2
2
treated with H O at various concentrations for 4 h, and 850 lM was finally selected
2
2
(showing about 60% viability) to examine the neuroprotective effects of the isolates
and vitamin C was used as a positive control. Cells were pretreated with 850 lM H O2
2
for 4 h and then removed the H O solution, treated with each isolates (5, 10, 20, 40
2
2
lM) for 48 h or cells were only treated with solates (5, 10, 20, 40 lM) for 48 h. After
the corresponding treatment, cell viability was measured using CCK-8 assay.
3.9. Statistical analysis
Data were presented as the mean ± SD of at least three separate experiments.
Statistical comparisons were analyzed by student’s t-test and p < 0.05 was considered
statistically significant.
4. Conclusion
In the present study, three previously undescribed dammarane-type saponins, namely
gypenoside J1, gypenoside J2 and gypenoside J3 as well as one known dammarane-
type saponin, gypenoside LVII, were isolated from G. pentaphyllum. All isolates showed
obvious protective effects on H O -induced oxidative stress in human neuroblastoma
2
2
SH-SY5Y cells. The study has provided candidate drugs for clinical use in many
neurodegenerative diseases.
Disclosure statement
No potential conflict of interest was reported by the authors.
Funding
This work was supported by the National Natural Science Foundation of China [grant number
8
1673692] and the Doctoral Student’s Independent Research Project of Minzu University of
China [grant number 181085].

8
S.-F. XING ET AL.
References
Ahmed T, Raza SH, Maryam A, Setzer WN, Braidy N, Nabavi SF, de Oliveira MR, Nabavi SM. 2016.
Ginsenoside Rb1 as a neuroprotective agent: a review. Brain Res Bull. 125:30–43.
Chen DJ, Liu HM, Xing SF, Piao XL. 2014. Cytotoxic activity of gypenosides and gynogenin
against non-small cell lung carcinoma A549 cells. Bioorg Med Chem Lett. 24:186–191.
Circosta C, De Pasquale R, Occhiuto F. 2005. Cardiovascular effects of the aqueous extract of
Gynostemma pentaphyllum Makino. Phytomedicine. 12:638–643.
Huang TH, Razmovski-Naumovski V, Salam NK, Duke RK, Tran VH, Duke CC, Roufogalis BD. 2005.
A novel LXR-alpha activator identified from the natural product Gynostemma pentaphyllum.
Biochem Pharmacol. 70:1298–1308.
Ky PT, Huong PT, My TK, Anh PT, Kiem PV, Minh CV, Cuong NX, Thao NP, Nhiem NX, Hyun JH,
et al. 2010. Dammarane-type saponins from Gynostemma pentaphyllum. Phytochemistry.
71:994–1001.
Lin CC, Huang PC, Lin JM. 2000. Antioxidant and hepatoprotective effects of Anoectochilus
formosanus and Gynostemma pentaphyllum. Am J Chin Med. 28:87–96.
Piao XL, Wu Q, Yang J, Park SY, Chen DJ, Liu HM. 2013. Dammarane-type saponins from
heat-processed Gynostemma pentaphyllum show fortified activity against A549 cells. Arch
Pharm Res. 36:874–879.
Shi GH, Wang XD, Zhang H, Zhang XS, Zhao YQ. 2018. New dammarane-type triterpene
saponins from Gynostemma pentaphyllum and their anti-hepatic fibrosis activities in vitro.
J Funct Foods. 45:10–14.
Tabner BJ, El-Agnaf OM, Turnbull S, German MJ, Paleologou KE, Hayashi Y, Cooper LJ, Fullwood
NJ, Allsop D. 2005. Hydrogen peroxide is generated during the very early stages of aggrega-
tion of the amyloid peptides implicated in Alzheimer disease and familial British dementia.
J Biol Chem. 280:35789–35792.
Takemoto T, Arihara K. 1986. Studies on the constituents of cucurbitaceae plants. XV. on the
saponin constituents of Gynostemma pentaphyllum MAKINO. Yakugaku Zasshi. 106:758–763.
Uttara B, Singh AV, Zamboni P, Mahajan RT. 2009. Oxidative stress and neurodegenerative
diseases: a review of upstream and downstream antioxidant therapeutic options. Curr
Neuropharmacol. 7:65–74.
Wang J, Yang JL, Zhou PP, Meng XH, Shi YP. 2017. Further new gypenosides from Jiaogulan
(Gynostemma pentaphyllum). J Agric Food Chem. 65:5926–5934.
Xie Z, Liu W, Huang H, Slavin M, Zhao Y, Whent M, Blackford J, Lutterodt H, Zhou H, Chen P,
et al. 2010. Chemical composition of five commercial Gynostemma pentaphyllum samples and
their radical scavenging, antiproliferative, and anti-inflammatory properties. J Agric Food
Chem. 58:11243–11249.
Xing SF, Jang M, Wang YR, Piao XL. 2016. A new dammarane-type saponin from Gynostemma
pentaphyllum induces apoptosis in A549 human lung carcinoma cells. Bioorg Med Chem Lett.
26:1754–1759.
Yonny ME, Rodriguez Torresi A, Cuyamendous C, Reversat G, Oger C, Galano JM, Durand T,
Vigor C, Nazareno MA. 2016. Thermal stress in melon plants: phytoprostanes and phytofurans
as oxidative stress biomarkers and the effect of antioxidant supplementation. J Agric Food
Chem. 64:8296–8304.