Invest Clin 65(1): 48 - 58, 2024 https://doi.org/10.54817/IC.v65n1a05
Corresponding author. Yun An. Department of Digestive Internal Medicine, Panyu District Traditional Chinese
Medicine Hospital, Guangzhou, China. Tel: +86 020 85926915. Email: anyun_2022@163.com
The mechanism of folic acid on N-methyl-
N’-nitro-N-nitrosoguanidine-induced chronic
atrophic gastritis through the PI3K/Akt
pathway.
Yun An1, Weigang Chen1, Yong Cao2, Boshen Chen1, Qiangbin Li1 , Xia Zhou1
and Weihan Huang1
1 Department of Digestive Internal Medicine, Panyu District Traditional Chinese
Medicine Hospital, Guangzhou,China.
2 Department of Traditional Chinese Medicine, Jinan University, Guangzhou, China.
Keywords: folic acid; chronic atrophic gastritis; N-methyl-N’-nitro-N-nitrosoguanidine
(MNNG); PI3K/Akt.
Abstract. Chronic atrophic gastritis (CAG) is a precancerous atrophic
gastritis of the stomach, which generates an urge to develop novel therapeu-
tic schedules. This study aimed to investigate the effect of experimental folic
acid administration on N-methyl-N’-nitro-N-nitrosoguanidine (MNNG)-induced
CAG through the PI3K/Akt pathway in rats. The rats were divided into a Model
Group, a Folic Acid Group and a Blank Group. Rats in the Model Group were
induced by MNNG and given 10 mL/kg/d distilled water by gavage, while rats
in the Folic Acid Group were induced by MNNG and given 5 mg/kg/d folic acid
suspension by gavage. As a control, rats in the Blank Group were given the
same amount of distilled water as MNNG and 10 mL/kg/d distilled water by
gavage. The levels of gastrin (GAS) and motilin (MTL) in serum were measured
by enzyme-linked immunosorbent assay (ELISA), and the mRNA and protein ex-
pressions were detected by quantitative polymerase chain reaction (q-PCR) and
Western blot. According to hematoxylin and eosin (H&E) pathological analysis,
there were inflammatory factors infiltration and derangement of mucosal epi-
thelial cells in the model group, while the gastric tissue injury in the folic acid
group was improved. Folic acid could decrease the content of GAS, increase the
content of MTL in the serum of the rats, and regulate the expression of PI3K
and AKT signal pathways. Folic acid can have a therapeutic effect on CAG by
reducing the concentration of GAS in serum and increasing the concentration
of MLT in serum. Our study would lay a theoretical foundation for using folic
acid to investigate new therapies for CAG in humans.
Folic acid for chronic atrophic gastritis 49
Vol. 65(1): 48 - 58, 2024
Mecanismo de acción del acido fólico en la gastritis atrófica
crónica inducida por N-Metil-N’-Nitro-N-Nitrosoguanidina
mediante la vía PI3K/Akt.
Invest Clin 2024; 65 (1): 48 – 58
Palabras clave: ácido fólico; gastritis atrófica crónica; N-metil-N’-nitro-N-
nitrosoguanidina (MNNG); PI3K/Akt.
Resumen. La gastritis atrófica crónica (CAG) es una condición precance-
rosa del estómago que refleja la necesidad urgente de desarrollar nuevos regí-
menes terapéuticos. Este estudio tiene como objetivo investigar el impacto del
ácido fólico sobre la CAG inducida en ratas por N-metil-N’-nitro-N-nitrosogua-
nidina (MNNG) a través de la ruta de señalización PI3K/Akt. Las ratas se divi-
dieron en tres grupos: Grupo Modelo, Grupo de Ácido Fólico y Grupo Control.
En el Grupo Modelo, las ratas fueron inducidas por MNNG y recibieron 10 mL/
kg/d de agua destilada mediante sonda gástrica, mientras que en el Grupo de
Ácido Fólico se indujo con MNNG y se les administró una suspensión de ácido
fólico de 5 mg/kg/d mediante sonda gástrica. En el Grupo Control, se admi-
nistró la misma cantidad de agua destilada que a las ratas en el Grupo Modelo,
y se suministró 10 mL/kg/d de agua destilada mediante sonda gástrica. Los
niveles séricos de gastrina (GAS) y motilina (MTL) se midieron mediante el
ensayo inmunoenzimático (ELISA), y las expresiones de ARNm y proteínas se
detectaron mediante reacción en cadena de la polimerasa cuantitativa (q-PCR)
y Western blot. Según el análisis patológico con tinción de hematoxilina y eo-
sina (H&E), se observó infiltración de factores inflamatorios y trastorno en las
células epiteliales de la mucosa en el Grupo Modelo, mientras que las lesiones
del tejido gástrico en el Grupo de Ácido Fólico mostraron una mejora. El ácido
fólico podría disminuir el contenido de GAS, incrementar el contenido de MTL
en el suero de las ratas, y regular la expresión de las rutas de señalización PI3K
y AKT. El ácido fólico puede tener un efecto terapéutico en la CAG al reducir
la concentración de GAS en el suero e incrementar la concentración de MTL.
Nuestro estudio proporcionaría una base teórica para el uso del ácido fólico en
la investigación de nuevas terapias para la CAG en humanos.
Received: 27-06-2023 Accepted: 08-09-2023
INTRODUCTION
Chronic atrophic gastritis (CAG) is a
precancerous atrophic gastritis of the stom-
ach, which remains a leading global health-
care problem 1. In China, the probability of
CAG turning into gastric cancer is 1.2%-
7.1% 2. In pathology, CAG develops into gas-
tric carcinoma through a series of processes,
such as atrophy of the inherent glands of
gastric mucosa, intestinal metaplasia and
atypical hyperplasia. Notably, early detection
and early treatment of CAG is a critical ap-
proach to block the further canceration of
the disease and improve the quality of life of
patients 3.
50 An et al.
Investigación Clínica 65(1): 2024
Folic acid, also known as vitamin M,
plays a crucial role in the synthesis of pro-
tein, nucleotide and pantothenic acid in
humans. It has been reported that a lack
of folic acid can lead to colitis and chronic
atrophic gastritis, which increases the risks
of gastrointestinal cancer 4. In addition, Lin
et al. 5 reported that the natural apoptosis
rate of gastric cancer cells was much high-
er in patients with gastric cancer given a
specific concentration of folic acid than in
those without intervention. Therefore, the
anti-cancer mechanism of folic acid may be
to regulate the expression of some cancer
cells to accelerate apoptosis.
The PI3K/AKT pathway is a signaling
pathway associated with proliferation, dif-
ferentiation and apoptosis, which regulates
the proliferation and survival of tumor cells
and plays an essential role in tumor cell mi-
gration and adhesion. It has been reported
that folic acid could produce positive effects
through the PI3K/AKT pathway in differ-
ent pathological conditions, such as colon
cancer, oral squamous cell carcinoma, and
so on6,7. Furthermore, folic acid could at-
tenuate the hypoxia-induced inflammatory
responses of THP-1 cells through inhibiting
the PI3K/Akt/HIF-1α pathway 8.
In this study, we aim to investigate the
effects of folic acid on chronic atrophic gas-
tritis rats through the PI3K/AKT pathway
and lay a preclinical foundation for folic acid
in treating CAG.
MATERIALS AND METHODS
Experimental materials
Animals: Specific Pathogen Free (SPF)
male Sprague Dawley (SD) rats, weighing
200-300g, purchased from the Guangzhou
University of Chinese Medicine Experimen-
tal Animal Center.
Reagents: MNNG (Guangzhou Kang-
ming Biotechnology Co., Ltd., batch number:
20210601), N1’-[2-[[5-[(dimethylamino)
methyl]-2-furanyl]methylthio]ethyl]-N1-
methyl-2-nitroethene-1,1-diamine (Guang-
dong Hengjian Pharmaceutical Co., Ltd.,
National Standard Word H44021173), ra-
nitidine (Guangdong Hengjian Pharmaceuti-
cal Co., Ltd., H44021173), folic acid tablets
(Fuzhou HAIWANGFU Pharmaceutical Co.,
Ltd., batch number: 21042810).
Materials and equipment: ELISA GAS
kit (Cat. MM-21284R1), MTweizL kit (Cat.
MM-0491R1), PI3K kit (Cat. MM-0427R1)
and Akt kit (Cat.MM-50624H1) were pur-
chased from Jiangsu enzyme-free Industry
Co., Ltd. (Yancheng, China), hematoxylin
and eosin staining solution (100ML, Bei-
jing Solebo Technology Co., Ltd., Beijing,
China). Semi-automatic rotary paraffin sec-
tioning machine (HM340E), Embedding
Workstation (Histosta), automatic dyeing
machine (Gemini AS), Rapid Tissue Pro-
cessor (STP120), refrigerated centrifuge
(FRESCO 70) and Multiskan SkyHigh Mi-
croplate Spectrophotometer (1510) were
purchased from Thermo Fisher Inc. (Massa-
chusetts, USA). Electric thermostatic drying
oven (Shanghai Jing Hong laboratory Instru-
ment Co.,Ltd., Shanghai, China), electronic
analytical balance (UX2200H, Shimatsu
Corporation, Tokyo, Japan), and optical mi-
croscope (CX-23, Olympus Corporation, To-
kyo, Japan).
Modeling and grouping
The model was established, and 30
SPF SD rats were randomly divided into
two groups. Ten rats were selected for nor-
mal feeding (NC Group), and the remaining
20 rats were used to establish the model.
MNNG-induced rats in the Model Group were
fed with 180 μg/mL MNNG and 0.003 g/mL
ranitidine hydrochloride once every three
days. At the same time, the rats in the blank
group were given the same amount of dis-
tilled water by gavage, and the other feeding
conditions were the same. Every six weeks,
one rat was selected from the blank group
and the model group for dissection, and
HE-stained sections were made to observe
the histomorphological changes of gastric
mucosa and test the effect of its modeling.
Folic acid for chronic atrophic gastritis 51
Vol. 65(1): 48 - 58, 2024
After successful modeling, the rats were di-
vided into three groups according to body
weight: Model Group (MC Group) and Folic
Acid Group (AC Group).
Method of administration
Rats in the Normal Group (NC Group)
and Model Group (MC Group) were given
10 mL/kg/d distilled water by gavage,
while the Folic Acid Group (AC group) was
given 5 mg/kg/d folic acid suspension by
gavage.
Specimen collection
After six weeks of treatment, the rats in
each group fasted and watered for two days
and then were anesthetized with ether, and
stomach and blood samples of the inferior
vena cava were taken. The blood samples of
each rat were centrifuged at 4°C 3500 rpm
for 15 min, and the supernatant was extract-
ed and preserved to detect the content of
GAS and MTL.
Histopathological examinations
Stomach samples were rinsed with
pre-cooled saline three times and fixed in
10% neutral formalin solution. After 24h,
specimens were dehydrated in ethanol and
xylene, respectively and then embedded in
paraffin wax. 5 μm thick serial slices were
obtained by microtome and stained with
hematoxylin-eosin (H&E). Histopathologi-
cal changes were determined by photogra-
phy with light microscopy, and 100×, 200×
magnifications were used in the microscopy
analysis. Anatomical scoring standards: 0,
no damage; 1, mucosal congestion and ede-
ma; 2, scattered swelling protrusions on the
mucosa; 3, mucosal mass with more pro-
trusions; 4, mucosal mass protruding into
patches. Microscopic pathological scoring
standards are described in Table 1. An av-
erage proportion was calculated from 5 re-
gions in each sample and used for statisti-
cal analysis.
Table 1
Microscopic pathological scoring standards.
Pathological
changes
0 1 2 3
Neutrophil
infiltration
none mild moderate severe
Lymphoid,
monocyte,
plasma cell
infiltration
none mild moderate severe
Gland
destruction
none mild moderate severe
Inflammatory
infiltration of
mucosal muscle
layer
none mild moderate severe
Enzyme-linked immunosorbent assays
The concentrations of GAS (96T) and
MTL (96T) in rats were determined accord-
ing to the instructions of the manufacturer
in the ELISA kit (Guangzhou Kangming Bio-
technology Co., Ltd., Guangzhou, China).
Quantitative PCR for mRNA expression
Tissue total RNA extraction: was ex-
tracted with Trizol (Invitrogen). The concen-
tration of total RNA was determined by a UV
photometer and dissolved in 20 μL of ster-
ilized double distilled water (DEPC-treated
DDH2O) with 1.5% agarose gel at 120 V
for 30 min, then RNA electrophoresis was
performed to detect the integrity of RNA.
mRNA reverse transcription: cDNA synthe-
sis was performed in strict accordance with
the instructions of the reverse transcription
kit (Guangzhou Ruizhen Biotechnology Co.,
Ltd., China). The reverse transcription con-
ditions were determined as 94 °C 25 min, 43
°C 5 min, and 50 °C 5 min in one cycle and
stored at -200 °C. PCR reaction of reverse
transcription products: PCR Kit (Guangzhou
Ruizhen Biotechnology Co., Ltd.), primers
were synthesized by Shanghai Bioengineer-
ing Technology Service Co., Ltd. The primer
sequences are described in Table 2. The reac-
52 An et al.
Investigación Clínica 65(1): 2024
tion conditions were as follows: 94 °C 2 min,
one cycle, 94 °C 30 sec, 56 °C 30 sec, 72°C 1
min, 35 total cycles; 72 °C Extension 4 min.
The internal reference reaction conditions
were 94 °C 30 sec, 55 °C 30 sec, 72 °C 1
min, 35 cycles, 72 °C 4 min. Electrophoresis
analysis of products: PCR detection products
were 1.2%. 5% agarose gel 80 V electropho-
resis about 60 min, using a gel image analyz-
er (produced by BIO-RAD company), using
Quantity One analysis software, the ratio of
the optical density of the amplified product
to that of β-actin was used as a parameter of
the expression level.
Western Blotting Assay
The protein was extracted with the
high-efficiency RIPA tissue/cell rapid lysate
containing 1 mmol/L PMSF (Dexian Xingye
Biotechnology Co. LTD, Guangzhou, China)
and the phosphatase inhibitor Cocktail III
(Guangzhou Kangming Biology Science and
Technology Co., LTD，Guangzhou, China).
It was quantified with the BCA Protein Assay
Kit (Guangzhou Baisheng Biology Science
and Technology Co., LTD, Guangzhou, Chi-
na). SDS-PAGE separated protein bands and
then transferred to a polyvinylidene fluoride
(PVDF) membrane (Guangzhou Hehua Tech-
nology Co., LTD, Guangzhou, China). After
being sealed in Tris-buffered saline (TBS)
containing 5% bovine serum albumin (BSA)
(Guangzhou Xunyi Biology Science and
Technology Co., LTD, Guangzhou, China) at
room temperature for 1 h, the membranes
were incubated with primary antibodies at
4°C overnight (Table 2), washed with TBS-
0.1% Tween 20 (TBST), and then incubated
with horseradish peroxidase-conjugated sec-
ond antibody (goat anti-rabbit IgG) at room
temperature for 1 h. GAPDH was used as the
internal reference, and the protein bands
were visualized and quantified by Image-pro
Plus 6.0 software.
Statistical methods
The data of each group were analyzed
using GraphPad Prism 8.0.2 statistical soft-
ware, and the specific experimental data
were expressed in the form of ± SD. The
homogeneity of variance test was performed
if the normality test conformed to the nor-
mal distribution. Data that did not conform
to the normal distribution were presented
as median (lower quartile, upper quartile)
[M (Q25, Q75)] using the Kruskal-Wallis
nonparametric test. p<0.05 for the differ-
ence was statistically significant. After the
variance was homogenized, the LSD test in
the one-way variance was used for analysis p
<0.05 means the difference was statistically
significant.
RESULTS
Effect of folic acid on gastric pathology
The anatomical images of rats are
shown in Fig. 1A. The gastric mucosa of
the model group was elastic, with edema,
verrucous process and hyperplasia, and the
mucosa was dark and white. Compared with
the model group, the gastric mucosa in
Table 2
Antibodies used
Antibodies Dilution Manufacturers Cat. no
Rabbit PI3 kinase 1:500 Affinity AF6242
Rabbit anti-PI3 kinase p110 beta 1:500 Affinity AF3242
Rabbit anti-AKT 1:500 Affinity AF6261
Phospho-AKT (Ser473) 1:500 SAB 11054
GAPDH monoclonal antibody 1:50,000 Proteintech 60004-1-Ig
Goat anti-rabbit IgG (H + L) 1:20,000 ZSGB-BIO ZB-2301
Folic acid for chronic atrophic gastritis 53
Vol. 65(1): 48 - 58, 2024
the folic acid group was improved, and the
gastric mucosa was still ruddy. According
to the pathological section of each group
of rats (Fig. 1B), the columnar cells in the
mucosa of the normal group were intact,
the muscular layer of the mucosa was ar-
ranged in the inner ring and outer ring, the
nuclei distributed orderly, and the mucosal
basal layer had no inflammatory infiltration,
there was no infiltration of neutrophil and
lymphocyte, and inflammatory infiltration
was found in the muscularis mucosa of the
gastric cancer model group, and the number
of glands in the lamina propria was signifi-
cantly decreased, in the positive group, the
columnar nuclei of the epithelial cells were
scattered and not closely arranged, and the
tissues were covered with lymphocyte, plas-
ma cells and neutrophil Simple columnar
epithelium, the lamina propria is slightly re-
duced, and the stroma is slightly loose with
a small amount of lymphocyte, plasma cells,
and neutrophil infiltration. Given the lack of
alterations in the NC group, the expression
of alterations in the other groups studied is
significant (Table 3).
Fig 1. Effect of folic acid on gastric histomorphology of CAG rats. (A) Representative morphology of
stomach image of rats. (B) Representative photomicrographs of gastric histopathology in rats. (HE
staining, 100×, 200×, Scale bar = 50 μm). N=5. NC, normal group; MC, model group; AC, folic acid
group.
54 An et al.
Investigación Clínica 65(1): 2024
Table 3
Effects of folic acid on pathological changes
of rat stomach tissue
Group Gross pathological
changes
Pathological
changes under
a microscope
NC 0.00(0.00,0.00) 0.00(0.00,0.00)
MC 3.00(2.50,3.50) 7.50(7.25,8.50)
AC 1.50(1.25,2.00)* 2.00(0.75,5.25)*
The median and quartile were used to calculate the
mean proportions from five regions in each sample,
considering that anatomic and pathological section
scores were non-normal distributions. NC is the Nor-
mal Group, MC is the Model Group, and AC is the
Folic Acid Group. Given the lack of alterations in the
NC group, the expression of alterations in the other
groups studied is significant. * p<0.05 vs. MC.
Effects of folic acid on MTL and GAS in
the serum of gastric cancer rats induced
by MNNG comprehensive method
According to Fig. 2A and 2B, com-
pared with the model group, the content of
MTL in the Folic Acid Group was increased
(p<0.05), while there is no statistical sig-
nificance in the content of GAS between the
Folic Acid Group and the Model Group.
Effect of folic acid on PI3Kand Akt in the
serum of gastric cancer rats induced by
MNNG comprehensive method
As shown in Fig. 2C, compared with the
model group, the content of PI3K of stom-
ach tissue in the Folic Acid Group was de-
creased (*p<0.05), and the content of Akt
in both the Normal Group and the Folic Acid
Group was decreased (**p<0.01).
Effect of folic acid on the mRNA
expression of PI3k/Akt/ mTOR2 in gastric
cancer rats
According to Fig. 2D, the mRNA expres-
sion of PI3K in the Model Group was higher
than the Normal Group and Folic Acid Group
(**p<0.01). In addition, there is no statisti-
cal significance in the mRNA expression of
Akt between the Folic Acid Group and The
Model Group, while the mRNA expression of
Akt in the Normal Group was lower than in
the Model Group (**p<0.01).
Effect of folic acid on PI3k/Akt pro-
tein expression in gastric cancer rats
As shown in Fig. 3A and 3B, compared
with the model group, the expression of
Fig. 2. The difference of GAS, MTL, PI3K and Akt
in rat serum and stomach tissue. (A) and
(B) Effects of folic acid on serum GAS and
MTL in CAG rats induced by MNNG compre-
hensive method. Levels of gastrin and moti-
lin in rat serum; (C) Levels of PI3K and Akt
in rat serum. The mRNA expression of PI3K
and Akt in rat serum ; (D) mRNA expres-
sion of PI3K and Akt in rat stomach tissue.
Data were shown as ± SD. N=5. Data
were presented using one-way analysis
of variance (ANOVA) followed by the
Bonferroni method. ** p<0.01 versus
model group; * p<0.05 versus model
group. NC, normal group; MC, model
group; AC, folic acid group.
Folic acid for chronic atrophic gastritis 55
Vol. 65(1): 48 - 58, 2024
phosphorylated PI3K protein in the gastric
tissue of the rats in the folic acid groups was
down-regulated (**p<0.01). The phosphory-
lated AKT protein expression in the rats’ gas-
tric tissue in the compound medium group
was significantly down-regulated (Fig. 3A
and 3C, **p<0.01).
DISCUSSION
CAG is a precancerous atrophic gastritis
of the stomach, but the pathogenesis of CAG
in modern medicine is not clear 1. Therefore,
the prevention and treatment of CAG and
the development of gastric precancerous le-
sions are essential issues. At present, there
are mainly two ways of treatment: drugs and
surgery. Drug therapy mainly includes en-
hancing gastrointestinal peristalsis, promot-
ing gastric emptying, reducing gastric acid
secretion, protecting gastric mucosa, and
using antibiotics to treat CAG with positive
Helicobacter pylori (Hp). Whereas surgi-
cal approaches mainly include endoscopic
treatment and general surgical treatment
3,9. According to clinical management, drug
therapy is the routine treatment for CAG, in-
cluding (Hp) eradication, acid suppression,
gastric mucosa protection, gastric motility
promotion, anti-anxiety/depression therapy,
vitamin, folic acid therapy, and so forth 9.
It has been reported that the changes
in MTL and GAS in the treatment process
fully reflected the improvement of gastroin-
testinal function and relief of gastrointes-
tinal symptoms 10. MTL lowers stomach qi,
regulates gastrointestinal transit complex
movement during the interdigestive period,
Fig. 3. Effect of folic acid on the protein expression of PI3K and Akt in CAG rats. (A). The WB protein bands
of PI3K, p-PI3K, Akt, p-Akt and GAPDH in rat gastric tissue. (B) The protein expression level of PI3K
and p-PI3K in rat gastric tissue. (C) The protein expression level of Akt and p-Akt in rat gastric tissue.
Data were shown as ± SD. N=5. Data were presented using one-way analysis of variance (ANOVA)
followed by the Bonferroni method. ** p<0.01 versus model group; * p<0.05 versus model group. NC,
normal group; MC, model group; AC, folic acid group.
56 An et al.
Investigación Clínica 65(1): 2024
and can increase colon movement 11. GAS
can promote antrum contraction, stimulate
the gastric and small intestinal digestive sys-
tem, promote the growth of gastric mucosa,
promote the secretion of water and electro-
lytes 12, improve the activity of the pyloric
pump, and contract gastrointestinal smooth
muscle cells, promoting gastric emptying.
Folic acid, also known as vitamin M, plays
a crucial role in synthesizing proteins, nucle-
otides and pantothenic acid in humans. It has
been reported that a lack of folic acid can
lead to colitis and chronic atrophic gastritis,
which increases the risks of gastrointestinal
cancer 4. In addition, Lin et al. 5 reported that
the natural apoptosis rate of gastric cancer
cells was much higher in patients with gas-
tric cancer given a specific concentration of
folic acid than in those without intervention.
Therefore, the anti-cancer mechanism of fo-
lic acid may be to regulate the expression of
some cancer cells to accelerate apoptosis. In
this study, we investigated the effect of folic
acid on gastric cancer model rats by animal
experiment. According to Fig. 1, the gastric
cancer model rats in the gastric mucosa
showed a lot of hyperplasias, verrucous protu-
berances into pieces, the mucosa white, dark,
a little erosion and other phenomena. After
treatment, after H&E staining, the patho-
logical sections of the model group were ana-
lyzed. The inflammatory factors infiltration
and derangement of mucosal epithelial cells
were found in the model group, which were
improved to some extent after treatment. Ac-
cording to the pathological analysis and score
of each group, the gastric tissue injury in the
folic acid group improved somewhat com-
pared with the model group. Subsequently,
we evaluated the Motilin (MTL) content in
each group of rats. Folic acid could increase
the MTL content in rats’ serum, promote the
gastrointestinal movement of rats, and im-
prove the pathological state of rats with gas-
tric cancer. The PI3K/AKT pathway is a sig-
naling pathway associated with proliferation,
differentiation and apoptosis, which regu-
lates the proliferation and survival of tumor
cells and plays an essential role in tumor cell
migration and adhesion. As shown in Fig.2C,
the levels of PI3K and Akt in the folic acid
group decreased, which may be related to the
inhibition of the development of cellular in-
flammation. As shown in Fig. 2D, the mRNA
expression of PI3K was decreased in the folic
acid group, which may be related to its pro-
motion of tumor cell apoptosis. As shown in
Fig. 3, Folic acid may down-regulate the ex-
pression of phosphorylated PI3K and Akt pro-
tein, accelerate the apoptosis of cancer cells,
and play a role in cancer inhibition.
In summary, folic acid can be therapeu-
tic on CAG, associated with the contents of
GAS and MLT in serum and the PI3K/Akt
signaling pathway. Our study will lay a theo-
retical foundation for using Folic acid to in-
vestigate new therapies for CAG in humans.
Ethical approval
The authors are accountable for all as-
pects of the work in ensuring that questions
related to the accuracy or integrity of any
part are appropriately investigated and re-
solved. Experiments were performed under
a project license (NO.: 2020041) granted
by the Animal Experimentation Ethics Com-
mittee of Panyu District Traditional Chinese
Medicine Hospital in compliance with na-
tional or institutional guidelines for the care
and use of animals.
ACKNOWLEDGEMENTS
The Basic and Applied Basic Research
Project from Guangzhou Science and Tech-
nology Bureau and Panyu District Hospital
of Traditional Chinese Medicine, Guangzhou
University of Chinese Medicine, supported
this work. We thank Prof. Cao Yong for super-
vision and guidance, Prof. Weigang Chen for
guidance in clinical work and case analysis,
Prof. Shaozhen Hou and her team for assis-
tance with mouse models and index testing,
and Dr. Qiangbin Li and Dr. Boshen Chen for
technical support.
Folic acid for chronic atrophic gastritis 57
Vol. 65(1): 48 - 58, 2024
Conflict of interest
The authors had no separate personal,
financial, commercial, or academic conflicts
of interest.
Availability of data and material
All data generated or analyzed during
this study are included in this published ar-
ticle.
Funding
This work was supported by the Guang-
zhou Science and Technology Program Proj-
ect (Project No.: 202102080643) “Study on
the Mechanism of Astragalus Guizhi Decoc-
tion on Precancerous Lesions in CAG Rats
Based on P13k-Akt-mTORC2 Pathway”.
ORCID numbers of authors
• Yun An (YA):
0000-0002-9438-2999
• Weigang Chen (WC):
0009-0007-9814-1037
• Yong Cao (YC):
0009-0004-5217-1298
• Boshen Chen (BC):
0009-0005-4367-4456
• Qiangbin Li (QL):
0009-0009-8546-734X
• Xia Zhou (XZ):
0009-0003-3073-3512
• Weihan Huang (WH):
0009-0006-9402-3052
Author contributions
Study conception and design: YA, WC,
YC, Data collection: BC, Data analysis and
interpretation: QL, WH, Drafting of the ar-
ticle: All authors. Critical revision of the ar-
ticle: All authors.
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