Anti-Obesity Effect of Lactobacillus gasseri BNR17 in
High-Sucrose Diet-Induced Obese Mice
Ji-Hee Kang*, Sung-Il Yun, Mi-Hee Park, Jun-Hong Park, So-Young Jeong, Han-Oh Park
R&D center, Bioneer Corporation, Daejeon, Republic of Korea
Previously, we reported that Lactobacillus gasseri BNR17 (BNR17), a probiotic strain isolated from human breast milk,
inhibited increases in body weight and adipocyte tissue weight in high-sucrose diet-fed Sprague-Dawley (SD) rats and
reduced glucose levels in type 2 diabetes mice. In the current study, we conducted further experiments to extend these
observations and elucidate the mechanism involved. C57BL/6J mice received a normal diet, high-sucrose diet or high-
sucrose diet containing L. gasseri BNR17 (109or 1010CFU) for 10 weeks. The administration of L. gasseri BNR17 significantly
reduced the body weight and white adipose tissue weight regardless of the dose administered. In BNR17-fed groups, mRNA
levels of fatty acid oxidation-related genes (ACO, CPT1, PPARa, PPARd) were significantly higher and those of fatty acid
synthesis-related genes (SREBP-1c, ACC) were lower compared to the high-sucrose-diet group. The expression of GLUT4,
main glucose transporter-4, was elevated in BNR17-fed groups. L. gasseri BNR17 also reduced the levels of leptin and insulin
in serum. These results suggest that the anti-obesity actions of L. gasseri BNR17 can be attributed to elevated expression of
fatty acid oxidation-related genes and reduced levels of leptin. Additionally, data suggested the anti-diabetes activity of L.
gasseri BNR17 may be to due elevated GLUT4 and reduced insulin levels.
Citation: Kang J-H, Yun S-I, Park M-H, Park J-H, Jeong S-Y, et al. (2013) Anti-Obesity Effect of Lactobacillus gasseri BNR17 in High-Sucrose Diet-Induced Obese
Mice. PLoS ONE 8(1): e54617. doi:10.1371/journal.pone.0054617
Editor: Kathrin Maedler, University of Bremen, Germany
Received July 8, 2012; Accepted December 13, 2012; Published January 30, 2013
Copyright: ? 2013 Kang et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Funding: This work was supported by High Value-Added Food Technology Development Program; Ministry for Food, Agriculture, Forestry and Fisheries,
Republic of Korea. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing Interests: All authors are employed by the Bioneer Corporation. Bioneer Co. has patents for Lactobacillus gasseri BNR17. This does not alter the
authors’ adherence to all the PLOS ONE policies on sharing data and materials, as detailed online in the guide for authors.
* E-mail: email@example.com
Obesity is caused by a multiple factors, including genetic,
metabolic, behavioral and cultural factors. More specifically, a high
fat intake and low energy expenditure are the main causes of
obesity, as well as metabolic disorders such as insulin resistance,
type 2 diabetes, and cardiovascular diseases [1,2]. A variety of
programs and treatments including drug therapeutics, surgical
intervention and dietary control for obesity management or
prevention have been developed; however, these are often
associated with safety issues. Therefore, the development of a safe
and effective dietary supplement to assist with body weight
management is essential.
Lactobacilli and bifidobacteria are representative probiotic
microorganisms that benefit human health through modulation
of the immune system , prevention of cancer , enhancement
of intestinal functions  and a hypocholesterolemic effect .
Recently, some studies have expended the functionality of
probiotics to obesity management. Some probiotics have been
demonstrated to have an anti-obesity property by regulating lipid
and glucose metabolism [7,8], producing conjugated linoleic acid
[9,10], reducing the adipocyte size and increasing the number of
small adipocytes in white adipose tissue , and regulating leptin
We have observed the effects of L. gasseri BNR17, a probiotic
strain isolated from human breast milk, on the high-sucrose diet-
fed SD rat and transgenic db/db mouse [13,14]. In those studies, L.
gasseri BNR17 suppressed the body weight and fat weight gain,
fasting and postprandial blood glucose, and improved oral glucose
tolerance. The purpose of the current study was to extend these
observations and elucidate the mechanism involved in the anti-
obesity activity of L. gasseri BNR17. We investigated the impact of
L. gasseri BNR17 on body weight gain, fat accumulation, and
mRNA expression of obesity-related genes in diet-induced obese
Materials and Methods
Animals and Experiment
Male C57BL/6J mice (6-week-old, n=8 per group) were
obtained from Central Lab Animal Inc. (Seoul, South Korea).
All animals were housed in standard plastic cages (two mice per
cage), and maintained under a 12-h light-dark cycle at constant
temperature and humidity (2361uC and 5565%, respectively)
with free access to food and water. This study was carried out in
accordance with the recommendations in the guide for the care
and use of the Animal, Plant and Fisheries Quarantine and
Inspection Agency (Republic of Korea). The protocol was
approved by the Committee on the Ethics of Animal Experiments
of the Bioneer Corporation (AEC-20081229-0004). Following
acclimatization for 1 week, the mice were fed a normal diet (ND)
(2918C, containing 6.0% fat and 18.5% protein by weight;
Koatech Animal Inc., Pyeongtaek, South Korea), or a high-
sucrose diet (HSD) (AIN-76A, 5.0% fat, 50.0% sucrose, 15.0%
cornstarch and 20.0% protein by weight; Central Lab Animal
Inc.), or high-sucrose diet and BNR17 109CFU (HSD+BNR17(9))
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or 1010CFU (HSD+BNR17(10)) for 10 weeks. L. gasseri BNR17
was prepared fresh daily and orally administered twice per day.
Body weight and food intake were measured once a week. At the
end of the 10-week treatment period, mice were killed by cervical
dislocation after blood gathering. Liver, spleen, kidney, and
adipose tissues (mesenteric, subcutaneous, epididymal, perirenal)
were dissected precisely and weighed. An in vivo CT analysis
(InveonTM, Siemens Medical Solutions USA Inc.) was carried out
prior the killing of animals under 1.5–2% isoflurane in O2
Real-time PCR Analysis
RNA was extracted from ,0.1 g of tissues using the RNeasy
Mini kit (Qiagen) for liver and RNeasy Lipid Tissue Mini kit
(Qiagen) for white adipose tissue, according to the manufacturer’s
protocols. cDNA was synthesized using the AccupowerH Rock-
etscriptTMCycle RT Premix kit from Bioneer (Daejeon, South
Korea). qPCR was performed using an Exicycler (Bioneer) with
AccupowerH 26 Greenstar qPCR Master Mix (Bioneer). Primer
sequences for the targeted mouse genes are listed in Table 1.
Endocrine peptides (ghrelin, GIP, GLP-1, glucagon, insulin,
leptin) were determined using a Bio-Plex suspension array system
(Luminex, Austin, USA). Metabolic parameters including glucose,
total cholesterol, HDL-cholesterol, and LDL-cholesterol levels in
serum were analyzed using a Clinical Analyzer 7020 (HITACHI,
Measurement of Adipocyte Size
Adipocyte sizes in the mesenteric, subcutaneous, epididymal
and perirenal adipose tissue were measured in paraffin-embedded
tissue. Briefly, adipocyte tissues were fixed in 10% neutral formalin
solution, embedded in paraffin, cut into 4-mm sections, and stained
with hematoxylin and eosin. Cell sizes were measured using
a DIXI3000 (Leica, Wetzlar, Germany).
The data were expressed as mean values with their standard
errors. Analyses were performed using pairwise t-tests and
Wilcoxon rank sum tests. Differences were considered to be
statistically significant at values of P,0.05.
L. gasseri BNR17 Inhibits High-sucrose Diet-induced Body
Weight Gain and Fat Weight Accumulation
High-sucrose diet feeding induced significant body weight gain
throughout the study period compared to the ND group (Figure 1A
and Table 2). The administration of BNR17 induced less body
weight gain than the HSD group, although not in a dose-
dependent manner. Food intake differed significantly between the
ND and HSD groups (Figure 1B and Table 2); whereas no
significant differences were observed in daily food intake between
the HSD and HSD+BNR17 groups. Moreover, energy intake
were similar for all groups. This suggests that BNR17 contributed
to the reduced body weight gain. Total cholesterol and LDL-
cholesterol in the HSD group and HSD+BNR17 groups increased
compared to the ND group; however, no significant reduction was
caused by BNR17 administration (Table 2). In addition, glucose
levels did not change with BNR17 administration. High-sucrose
diet also induced increased adipose tissue weight as compared with
normal diet feeding (Table 2). BNR17 administration significantly
suppressed the increase of fat mass in all white adipose tissues,
including mesenteric, subcutaneous, epididymal and perirenal
adipose tissue (Table 2). Further, CT imaging showed a significant
reduction in body fat profile with BNR17 treatment (Figures 1C
and D). Moreover, HE staining of white adipose tissues revealed
that supplementation with BNR17 was associated with a significant
reduction in average adipocyte size in mesenteric, subcutaneous,
epididymal and perirenal adipose tissues, as compared with the
HSD group (Figures 1E and F).
Table 1. Primer sequences of mouse mRNA.
Target gene Forward Primer (59–39)Reverse Primer (59–39) Ref.
ANGPTL4 AAAGAGGCTGCCCGAGAT TCTCCCCAACCTGGAACA
PPARa, peroxisome proliferator-activated receptor a; PPARd, peroxisome proliferator-activated receptor d; CPT, carnitine palmitoyl-transferase; ACO, acyl CoA oxidase;
UCP3, uncoupling proteins3; GLUT4, glucose transporter 4; SREBP-1c, sterol regulatory element-binding protein-1c; ACC, acetyl-CoA carboxylase; FAS, fatty acid
synthetase; PPARc, peroxisome proliferator-activated receptor c; LPL, lipoprotein lipase; TNF-a, tumor necrosis factor-a.
Anti-Obesity Effect of Lb. gasseri BNR17
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Anti-Obesity Effect of Lb. gasseri BNR17
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L. gasseri BNR17 Affects the mRNA Expression of Obesity
and Diabetes-related Genes in Liver and White Adipose
The effect of BNR17 on the expression of obesity-related genes
was investigated using real-time RT-PCR. The mRNA expres-
sions of ACO, CPT1, PPARa, PPARd and ANGPTL4 were
significantly higher in the BNR17 groups compared to the HSD
group (Figure 2). Furthermore, mRNA expressions of ACC and
SREBP-1c showed tendencies to be lower in BNR17 groups.
The mRNA expressions of adiponectin, UCP3, LPL, PPARc
and TNF-a in white adipose tissue were measured. There were no
significant differences between the HSD and BNR17-fed groups
(Figure 3). However, the mRNA expression of GLUT4 was higher
in the BNR17 groups compared with the HSD group.
L. gasseri BNR17 Reduces the Levels of Leptin and Insulin
The effect of BNR17 on the gastrointestinal hormones involved
in body weight control was investigated. The level of leptin
increased in the HSD group compared to the ND group; however
it decreased in BNR17-fed groups (Figure 4). Similarly, the level of
insulin was significantly lower in BNR17-administered mice.
Levels of other hormones among the HSD group and BNR17-fed
groups were not different.
Although there was no difference in food and energy intake
between the HSD group and BNR17 groups (Figure 1B and
Table 2), the increase in body weight was suppressed in the
BNR17 groups (Figure 1A and Table 2). There was a significant
reduction in subcutaneous and abdominal fat mass in BNR17-fed
groups compared to the HSD group (Figure 1C and D).
Subcutaneous fat and abdominal fat are the major types of white
adipose tissue. Abdominal obesity is associated with increased risk
of insulin resistance and cardiovascular diseases, whereas increased
subcutaneous fat correlates with a favorable plasma lipid profile
[16,17]. Indeed, the mean adipocyte sizes of all white adipose
tissues were remarkably reduced in BNR17-fed mice (Figures 1E
and F). Subcutaneous adipocytes are the main source of leptin and
adiponectin . Leptin is an adipocyte hormone that controls
body weight by regulating food intake and energy expenditure
[18,19]. Leptin concentrations are correlated with the percentage
of body fat; higher serum levels have been found in obese
individuals compared with non-obese individuals . BNR17
suppressed the elevation of plasma leptin (Figure 3), suggesting
Figure 1. L. gasseri BNR17 supplementation decreases high-sucrose diet-induced body weight gain and fat mass accumulation. (A)
Change in body weight, (B) change in food intake, (C) representative CT scanning images of abdominal (left) and whole body (right) fat accumulation
(in black) at 10 weeks (D) correspond to the volume of subcutaneous and abdominal fat, (E) representative adipose tissue-staining images in mice of
four groups, (F) adipocyte mean area (mm2). Data represent the means 6 SD. Pairwise t-test: *P,0.05, **P,0.01, ***P,0.001 versus the ND group;
#P,0.05,##P,0.01,###P,0.001 versus the HSD group.
Table 2. Body weight, fat weight and organs weight of mice fed the experimental diets for 10 weeks.
ND HSD HSD+ +BNR17(9)HSD+ +BNR17(10)
Initial body weight (g)22.4161.0622.8861.20 22.4461.19 22.9060.77
Final body weight (g)27.6361.77 30.5961.46**27.9861.93##
3.1560.20 2.5760.15***2.5860.14*** 2.4760.16***
9.7560.63 9.7460.56 9.7860.53 9.3660.60
Mesenteric fat pad (g) 0.2760.100.4460.10**0.2960.08##
Subcutaneous fat pad (g) 0.6460.101.1560.22***0.7360.15###
Epididymal fat pad (g)0.7860.171.1160.23**0.8060.20##
Perirenal fat pad (g)0.4360.120.6560.14**0.4760.14#
Liver weight (g) 1.1660.131.1860.091.0160.09*,##
Spleen weight (g)0.1660.030.1860.020.1560.02#
Kidney weight (g)0.3060.020.2960.010.2860.020.2960.02
Cholesterol140.57612.88 192.00624.60** 177.63619.30**188.18618.88**
Glucose 209.63630.29204.00632.70 200.06662.73*214.21656.52
C57BL/6J mice were fed a normal diet (ND), a high-sucrose diet (HSD) or a HSD containing L. gasseri BNR17 (109or 1010CFU) for 10 weeks. After measurement of body
weight and feed intake, the white adipose tissue, liver, spleen and kidney were removed and weighed. Data represent the means 6 SD of eight mice per group. Pairwise
***P,0.001 versus the ND group;
###P,0.001 versus the HSD group.
Anti-Obesity Effect of Lb. gasseri BNR17
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that the reductions in fat mass and body weight are associated with
a reduction in leptin. Similar effects have been observed in other
studies [9,20,21]. For the liver, the weight reduction were observed
in BNR17 groups (Table 2), however HE staining and O-red
staining of liver tissue did not show any changes between groups
(Data not shown).
In this study, glucose was not change between groups. In the
paper that investigated the role of fatty acid composition in the
development of metabolic disorders in sucrose-induced obese
Figure 2. L. gasseri BNR17 affects mRNA expression in the liver. C57BL/6J mice were given ND, HSD, or HSD containing BNR17 (109or
1010CFU) for 10 weeks. The liver was then removed and mRNA expression was measured by real-time RT-PCR using b-actin as a housekeeping gene.
Data represent the means 6 SD. Pairwise t-test: *P,0.05, **P,0.01, versus the ND group;#P,0.05,##P,0.01 versus the HSD group.
Figure 3. L. gasseri BNR17 affects mRNA expression in white adipose tissue. C57BL/6J mice were given ND, HSD, or HSD containing BNR17
(109or 1010CFU) for 10 weeks. The white adipose tissue was then removed and mRNA expression was measured by real-time RT-PCR using b-actin as
a housekeeping gene. Data represent the means 6 SD. Pairwise t-test: *P,0.05, **P,0.01 versus the ND group;#P,0.05 versus the HSD group.
Anti-Obesity Effect of Lb. gasseri BNR17
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