Camellia Oil (Camellia oleifera Abel.) Modifies the Composition of Gut

Subscriber access provided by UNIVERSITY OF TOLEDO LIBRARIES

Bioactive Constituents, Metabolites, and Functions

Camellia Oil (Camellia oleifera Abel.) Modifies the Composition of the Gut Microbiota and Alleviates Acetic Acid-induced Colitis in Rats Wei-Ting Lee, Yu-Tang Tung, Chun-Ching Wu, Pang-Shuo Tu, and Gow-Chin Yen J. Agric. Food Chem., Just Accepted Manuscript • DOI: 10.1021/acs.jafc.8b02166 • Publication Date (Web): 13 Jun 2018 Downloaded from http://pubs.acs.org on June 14, 2018

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 36

Journal of Agricultural and Food Chemistry

1

Camellia Oil (Camellia oleifera Abel.) Modifies the Composition of the Gut

2

Microbiota and Alleviates Acetic Acid-induced Colitis in Rats

3

Wei-Ting Lee,†,∇ Yu-Tang Tung,‡, ∇ Chun-Ching Wu,† Pang-Shuo Tu,† and Gow-

4

Chin Yen*†,§

5

6

Department of Food Science and Biotechnology, National Chung Hsing University,

7

145 Xingda Road, Taichung 40227, Taiwan

8

Graduate Institute of Metabolism and Obesity Sciences, Taipei Medical University,

9

250 Wu-Hsing Street, Taipei 110, Taiwan

10

§ Institute of Food Safety, National Chung Hsing University, 145 Xingda Road,

11

Taichung 40227, Taiwan

12

13

∇

14

*Author to whom correspondence should be addressed.

15

Tel: 886-4-2287-9755, Fax: 886-4-2285-4378,

16

E-Mail: [email protected]

17

RUNNING TITLE: Camellia Oil Reduces Acetic Acid-induced Ulcerative Colitis

18

KEYWORDS: gut microbiota, camellia oil, olive oil, acetic acid, inflammatory bowel

19

disease, ulcerative colitis

These authors contributed equally to this work.

20 21

1

ACS Paragon Plus Environment


22

ABSTRACT

23

Ulcerative colitis (UC), one type of chronic inflammatory bowel disease (IBD), is a

24

chronic and recurrent disorder of the gastrointestinal (GI) tract. As camellia oil (CO) is

25

traditionally used to treat GI disorders, this study investigated the role of CO on acetic

26

acid-induced colitis in the rat. The composition of the gut microbial community is

27

related to many diseases, thus, this study also investigated the effects of CO on the

28

composition of the gut microbiota. The rats were fed a dose of 2 mL/kg body weight

29

CO, olive oil (OO), or soybean oil (SO) once a day for 20 days, and the gut microbiota

30

was analyzed using 16S rRNA gene sequencing. Results of the gut microbiota

31

examination showed significant clustering of feces after treatment with CO and OO;

32

however, individual differences with OO varied considerably. Compared to SO and

33

OO, the intake of CO increased the ratio of Firmicutes/Bacteroidetes, the α-diversity,

34

relative abundance of the Bifidobacterium, and reduced Prevotella of the gut

35

microbiota. On day 21, colitis was induced by a single transrectal administration of 2

36

mL of 4% acetic acid. However, pretreatment of rats with CO or OO for 24 days

37

slightly enhanced antioxidant and antioxidant enzyme activities, and significantly

38

reduced inflammatory damage and lipid peroxidation, thus ameliorating acetic acid-

39

induced colitis. These results indicated that CO was better able to ameliorate

40

impairment of the antioxidant system induced by acetic acid compared to OO and SO,

41

which may have been due to CO modifying the composition of the gut microbiota or

42

CO being a rich source of phytochemicals.

43

2


Page 2 of 36

Page 3 of 36


44

INTRODUCTION

45

The gut microbiota plays an essential role in human and animal health, and thus many

46

researchers are interested in modulating its composition to benefit the host.1

47

Modulation of the gut microbiome benefits many diseases, including inflammatory

48

bowel disease (IBD), gastrointestinal (GI) cancers, obesity, type 2 diabetes, hepatic

49

steatosis, and allergic airway disease.2-4 Thus, the host diet has a critical impact on the

50

composition of the gut microbiota5, and changes in the gut ecology can affect

51

inflammatory and metabolic properties and thereby host physiology.6

52

Crohn's disease (CD) and ulcerative colitis (UC) are the main types of chronic

53

inflammatory bowel disease (IBD) which are chronic progressive diseases with

54

persistent inflammation of the bowel. However, the incidence and prevalence of IBD

55

are increasingly worldwide.7 To date, the pathogenesis of IBD is not clearly

56

understood, but it has been linked to genetic, immunological, and environmental

57

factors.8 Previous studies showed that increased antioxidant enzymes can metabolize

58

oxidative toxic intermediates produced by IBD.10,11 Oxidative stress plays a vital role

59

in initiation and progression of IBD.9 Furthermore, the characteristic feature of acetic

60

acid-induced colitis in an animal model is also an imbalance between oxidant and

61

antioxidant substances.9 Currently, common drugs have incomplete efficacy, and they

62

are unable to maintain long-term clinical remission.10,12,13 Thus, exploring new

63

attractive therapeutic alternatives for curing IBD is critical. In addition, the long-term

64

use of pharmaceutical drugs results in numerous adverse effects.14 Therefore, desirable

65

therapeutic treatments such as nutritional or dietary products with antioxidant abilities

66

are suggested for treating such diseases.

67

Camellia oleifera Abel. is widely distributed in tropical and subtropical regions of

68

Asia, and its oil is an important edible oil in Taiwan and China. As a traditional 3



69

remedy, it is used to treat gastrointestinal (GI), lung, and kidney diseases. Camellia oil

70

(CO) is rich in several phytochemicals such as oleic acid (C18:1), linoleic acid

71

(C18:2), palmitic acid (C16:0), squalene, vitamin E, and flavonoids.15 Tu et al.16

72

showed that CO can reduce lipid peroxidation, apoptosis-related proteins,

73

proinflammatory cytokines, and nitric oxide production and increase antioxidant

74

enzyme activities, heat shock proteins, and prostaglandin E2 production, and thus

75

alleviate damage to the gastric mucosa by ethanol. Cheng et al.17 showed that CO has

76

the potential to ameliorate GI mucosal injury as evidenced by significant reductions in

77

inflammation, impairment of the antioxidant system, and oxidative damage induced by

78

ketoprofen.

79

Acetic acid induced-colitis is usually applied and easily inducible model. It is the

80

IBD model that bears close resemblance to human IBD in terms of pathogenesis,

81

histopathological features, and inflammatory mediator profile.9 However, the

82

protective effect of CO against acetic acid-induced colitis still lacks relevant support

83

from the scientific literature. Hence, the aim of this study was to evaluate the effects of

84

CO on the composition of the gut microbiota and acetic acid-induced colitis in SD rats.

85 86

MATERIALS AND METHODS

87

Preparation of Oil. Commercial Camellia oil (CO), commercial extra virgin

88

olive oil (OO) from Lakonia Greek, and commercial refined soybean oil (SO) were

89

purchased from the HsinI Country Farmer’s Association (Nantou, Taiwan), Amway

90

Taiwan Company (Taipei, Taiwan), and Taisugar Company (Tainan, Taiwan),

91

respectively. All oil samples were stored in airtight containers at 4 °C until further use.

92

4


Page 4 of 36

Page 5 of 36


93

Animal Treatment Procedures. Male Sprague-Dawley (SD) rats (aged 6 weeks

94

and weighing 188 ± 12 g) were purchased from the Livestock Research Institute

95

(Taipei, Taiwan) under specific pathogen-free (SPF) conditions. All animals were fed

96

a chow diet (Lab 5001, vendor info) and distilled water ad libitum and were

97

maintained on a regular 12-h light/dark cycle at 60%~70% humidity and room

98

temperature (22 ± 2°C). The experimental animals were given 1 week to acclimatize to

99

the environment and diet. All animal experimental protocols were approved by the

100

Institutional Animal Care and Use Committee (IACUC) of National Chung Hsing

101

University, Taichung, Taiwan (IACUC approval no: 104-130R2).

102

In this study, the effects of CO on the composition of the gut microbiota and acetic

103

acid-induced colitis in SD rats were evaluated. In the first part, 30 rats were randomly

104

assigned to three groups (n = 6): a group receiving SO at a dose of 2 mL/kg body

105

weight (BW) by gastric gavage (n = 18) for 20 days (SO group), a group receiving CO

106

at a dose of 2 mL/kg BW by gastric gavage (n = 6) for 20 days (CO group), and a

107

group receiving OO at a dose of 2 mL/kg BW by gastric gavage (n = 6) for 20 days

108

(OO group). For this study, the dose of CO and OO was used according to Tu et al.16.

109

On the 20th day of treatment, feces were taken from all animals (for bacterial DNA

110

extraction and 16S ribosomal (r)RNA sequencing). In the second part, on the 20th day,

111

the rats in the SO group (n = 18) were randomly assigned to three groups (n = 6): one

112

receiving soybean oil (SO) at a dose of 2 mL/kg BW by gastric gavage plus the

113

transrectal administration of 2 mL of saline (Control group), one receiving SO at a

114

dose of 2 mL/kg BW by gastric gavage plus the transrectal administration of 2 mL of

115

4% acetic acid (AA group), and one receiving oral administration of sulfasalazine

116

(SASP) at a dose of 500 mg/kg BW by gastric gavage plus the transrectal

117

administration of 2 mL of 4% acetic acid (AA+SASP group). The CO (n = 6) and OO 5



118

groups (n = 6) were individually assigned to a group receiving oral administration of

119

CO and OO, respectively, at a dose of 2 mL/kg BW by gastric gavage plus the

120

transrectal administration of 2 mL of 4% acetic acid (AA+CO group and AA+OO

121

group). All of these treatments (SO, CO, and OO) were given once a day for 24

122

consecutive days by oral gavage. Rats in the AA+SASP group were pretreated orally

123

with SO for 24 days and then were treated with 500 mg/kg BW SASP on days 21~24

124

for 4 days. Colitis was induced by the transrectal administration of acetic acid once on

125

day 21. On day 21, rats were anesthetized by ether inhalation, and the tip of a soft

126

catheter (2 mL of saline for control group or 2 mL of 4% acetic acid for AA group)

127

was inserted up to 8 cm proximal to the anus after removing distal stools. The rats

128

were maintained in a head-down position for 30 s to prevent leakage. At the end of the

129

experiment (day 24), each rat was anesthetized, and the colon was immediately

130

perfused with ice-cold 0.90% w/v of NaCl, then carefully removed, rinsed in ice-cold

131

0.90% w/v of NaCl, blotted dry, and weighed. All samples were stored at -80 °C for

132

further assays.

133 134

Bacterial DNA Extraction and 16S rRNA Sequencing. Fecal samples were

135

collected on day 20. After collection, fecal samples were immediately stored at -80 °C

136

for further DNA extraction. Bacterial DNA was extracted with a Qiagen DNA Mini

137

Kit (Qiagen, city, MD, USA). Briefly, bacterial DNA yielded from samples was for

138

directly used in polymerase chain reaction (PCR) assays and 16S rRNA gene

139

sequencing. The amount and quality of isolated DNA were determined with a

140

NanoDrop ND-1000 analyzer (Thermo Scientific, Wilmington, DE, USA). Extracted

141

DNA was stored at -80 °C prior to 16S rRNA sequencing. The hypervariable V3-V4

142

region of the bacterial 16S rRNA gene was amplified using a PCR with bar-coded 6


Page 6 of 36

Page 7 of 36


143

universal primers 341F (F, forward primer; 5’-CCTACgggNggCWgCAg-3’) and 805R

144

(R, reverse primer; 5’-gACTACHCgggTATCTAATCC-3’). Library construction and

145

sequencing of amplicon DNA samples were carried out by Germark Biotechnology

146

Co., Ltd (Taichung, Taiwan). A pair-end library (insert size of 465 bp for each sample)

147

was constructed with a TruSeq Nano DNA Library Prep kit (Illumina, San Diego, CA,

148

USA), and high-throughput sequencing was performed on an Illumina MiSeq 2000

149

sequencer with a MiSeq Reagent Kit v 3 (Illumina).

150 151

Sequencing Reads Quality Control and Analysis. On a per-sample basis, pair-

152

end reads were merged using USEARCH (vers. 8.0.1623), with minimum overlap of

153

read pair set at 8 base pairs (bp).18 Merged reads were quality-filtered with Mothur

154

(vers. 1.35.1) to remove reads shorter than 400 bp or longer than 550 bp, as well as

155

reads with a minimum average quality score of < 27.19 In addition, reads containing an

156

ambiguous base or homopolymer exceeding 8 bp were excluded. Chimeras were

157

detected using USEARCH (in the reference mode and 3% minimum divergence).

158

Quality-filtered and non-chimeric reads were analyzed (by the UPARSE pipeline) to

159

generate operational taxonomic units (OTUs) per sample (at a 97% identity level).20

160

Representative OTU sequences were searched against the Greengenes 13_5 database

161

using USEARCH global alignment to identify the corresponding taxonomy of the best

162

hit. Any OTU without a hit or with only a weak hit, i.e., with a function [(% sequence

163

identity + % alignment coverage)/2] of < 93, was excluded from further analysis.21 All

164

statistical analyses were performed using R software (http://www.r-project.org/),

165

unless otherwise specified. Diversity indices (e.g., Observed, Chao1, and Simpson)

166

were estimated using the R package phyloseq.22 Hierarchical clustering (via a

167

complete-linkage algorithm) of the microbiomes was conducted using the Bray-Curtis 7



168

distance of OTU-level relative abundance profiles, based on which principal

169

component analysis (PCA) was also performed using the R package, ade4.23 The

170

bioinformatics analyses mentioned above were carried out by Germark Biotechnology

171

Co., Ltd (Taihung, Taiwan).

172 173

Pathological Histology. Colon tissues were fixed in 10% buffered formaldehyde,

174

formally embedded in paraffin, and sectioned. Sections were examined using

175

hematoxylin and eosin (H&E) staining according to a previously described method.24

176

A histological injury score of colon tissues was assessed, and the degree of lesions was

177

graded from one to five depending on the severity: 1 = minimal (< 1%); 2 = slight

178

(1%~25%); 3 = moderate (26%~50%); 4 = moderate/severe (51%~75%); and 5 =

179

severe/high (76%~100%).

180 181

Preparation of Colon Homogenate. The colon was extracted as previously

182

described17 with slight modifications. Finally, colon homogenates were collected and

183

stored at -80 °C until being assayed.

184 185

Analysis of the Total Protein Concentration. The total protein concentration of

186

colon homogenates was determined colorimetrically using a commercial protein

187

reagent kit (Bio-Rad, Hercules, CA, USA).

188 189

Measurement of Superoxide Dismutase (SOD), Glutathione (GSH), and

190

Thiobarbituric Acid-Reactive Substances (TBARSs). The SOD activity, and GSH

191

and TBARS contents in colon homogenates were assayed according to a previous

192

method described by Cheng et al.17 8


Page 8 of 36

Page 9 of 36


193 194

Determination of Myeloperoxidase (MPO) Activity. In ulcerative colitis,

195

inflammation activates MPO-containing phagocytes in the inflamed intestine.25 Thus,

196

MPO activity is an important index of inflammatory damage.26 MPO activity of colon

197

homogenates was measured spectrophotometrically using hydrogen peroxide and

198

O‑dianisidine dihydrochloride as substrates with the absorbance at 460 nm as per a

199

previously described method by Krawisz et al.26

200 201

Statistical Analysis. Experimental data are expressed as the means ± standard

202

deviation (SD) (n = 6). An analysis of variance (ANOVA) was employed to calculate

203

differences between multiple groups with Duncan’s test. A p value < 0.05 was

204

considered statistically significant.

205 206

RESULTS

207

Effect of CO on the Gut Microbiota.

208

We analyzed the gut microbiota composition using the 16S rRNA gene in SO-,

209

CO-, and OO-treated rats and observed dramatic changes in the microbial ecology

210

when treated with different edible oils (SO, CO, and OO) for 20 days. A PCA showed

211

that rats clustered into relatively distinct groups based on different oils (SO, CO, and

212

OO) (Figure 1A). Results of the gut microbiota determination showed significant

213

clustering of feces between treatments with CO and SO; however, individual

214

differences of OO-treated rats varied considerably.

215

Alpha-diversity indexes of richness (observed and Chao1) were slightly increased

216

in CO-treated rats compared to OO- and SO-treated rats (Figure 1B, C). The Simpson

217

index, an alpha-diversity index of richness and evenness, was affected by the different 9



Page 10 of 36

218

types of edible oils, as shown by a significant increase in the diversity of the gut

219

microbiota in rats treated with CO compared to those treated with SO (Figure 1D).

220

Figure 1E shows that the overall compositions of the gut microbiome in SO- and OO-

221

treated rats were dominated by the phyla Firmicutes (59% for SO-treated rats and 62%

222

for OO-treated rats) and Bacteroidetes (33% for SO-treated rats and 31% for OO-

223

treated rats), in accordance with previous reports of gut microbiome compositions of

224

mice28,29. Other phyla detected included the Verrucomicrobia, Proteobacteria, and

225

Actinobacteria. However, CO-treated rats had reduced members of the phylum

226

Bacteroidetes and increased members of the phylum Firmicutes compared to OO- and

227

SO-treated rats.

228

Figure 2 shows distinct gut microbiota compositions of CO rats compared to rats

229

fed SO (Figure 2A) or OO (Figure 2B). As shown in Figure 2A, the linear

230

discriminant analysis (LDA) effect size (LEfSe) indicated that the genus Prevotella

231

was higher in SO-treated rats compared to CO-treated rats, while the Actinobacteria

232

(Bifidobacterium, Adlercreutzia, and Collinsella), Bacteroidetes (Bacteroides and

233

Odoribacter), Firmicutes (Bacillaceae and Christensenellaceae), and Proteobacteria

234

(Haemophilus) were higher in CO-treated rats compared to SO-treated rats (Figure

235

2A).

236

(Bifidobacterium)

237

Mogibacteriaceae) compared to OO-treated rats. In addition, OO-treated rats had

238

higher Bacteroidetes (Prevotella) and Proteobacteria (Pasteurellaceae) compared to

239

CO-treated rats.

Figure

2B

shows and

that

CO-treated

Firmicutes

rats

(Turicibacter,

had

higher

Actinobacteria

Peptostreptococcaceae,

and

240 241

Effect of CO on the Pathological Histology of Acetic Acid-Induced Colitis in Rats.

10


Page 11 of 36


242

In the animal model, acetic acid was employed to induce colitis. Figure 3A

243

revealed regular colonic mucosa with epithelium, crypts, and submucosa in the control

244

group. Acetic acid-treated rats demonstrated wide areas of epithelial and goblet cell

245

loss and severe neutrophil infiltration, ulcers, distortion of crypt architecture, and crypt

246

abscesses. However, the colitis rats treated with SASP, CO, and OO could ameliorate

247

acetic acid-induced hemorrhage damage in the colon. In acetic acid-treated rats, 3 days

248

after the induction of colitis, the hemorrhage damage score was 25.7 ± 1.5. However,

249

treatment with SASP, CO, and OO for 24 days significantly accelerated reductions in

250

the hemorrhage damage of 48.7%, 36.7% and 16.9%, respectively, compared to the

251

acetic acid-alone group (p < 0.05) (Figure 3B). Thus, pretreatment with CO and OO

252

could alleviate acetic acid-induced hemorrhagic damage.

253

Figure 4 and Table 1 show the protective effect of CO against acetic acid-

254

induced colitis using H&E staining. A histological evaluation showed a normal colon

255

with an intact mucosal layer and normal intestinal epithelial lining (Figure 4A-C).

256

Acetic acid instillation into the colon induced erosion of the surface epithelium,

257

hemorrhaging, edema, and acute inflammation of the colon wall (Figure 4D-F).

258

However, rats pretreated with CO and OO revealed mild acute inflammation, crypt

259

damage, and a slight disruption of the epithelial lining (Figure 4J-O). In addition, as

260

shown in Table 1, CO, OO, and SASP significantly reduced the injury score compared

261

to those in the acetic acid-alone group (p < 0.05).

262 263

Effect of CO on Antioxidant Enzymes, Antioxidants, and Lipid Peroxidation and

264

in Acetic Acid-Induced Colitis of Rats.

265

As shown in Figure 5A and 5B, the transrectal administration of acetic acid

266

resulted in significant reductions in levels of SOD and GSH in the colon (p < 0.05). 11



267

However, treatment with SASP significantly increased SOD and GSH levels in the

268

colon compared to the acetic acid-alone group (p < 0.05). Moreover, there were slight

269

increasing trends in SOD and GSH after pretreatment with CO or OO, although they

270

did not reach a significant difference with the acetic acid-alone group. As shown in

271

Figure 5C and 5D, levels of MDA and MPO both significantly increased after

272

transrectal administration of acetic acid compared to the control group (p < 0.05).

273

However, pretreatment with CO and OO remarkably reduced MDA and MPO levels in

274

the colon compared to those in the acetic acid-alone group (p < 0.05). The results

275

indicated CO and OO had the similar ability to ameliorate impairment of the

276

antioxidant system induced by acetic acid.

277 278

DISCUSSION

279

The gut microbial composition of CO-, OO-, and SO-treated rats were elucidated

280

through high-throughput DNA sequencing of 16S rRNA amplicons after 20 days of

281

feeding of edible oils. For the Simpson diversity index, SO and CO respectively

282

resulted in the least and most diverse gut microbiota (Figure 1D). This trend was

283

somewhat reflected in the other diversity metrics (Observed and Chao1-α) (Figure 1B,

284

C). Thus, the gut microbiota of CO-treated rats significantly increased in diversity

285

compared to SO-treated rats. Caesar et al.30 showed a significant decrease in the

286

phylogenetic diversity in samples from mice fed lard oil versus fish oil. Ou et al.31

287

showed that prebiotics such as feruloylated oligosaccharides significantly increased the

288

bacterial richness and diversity. However, the microbiome of IBD or CD patients had a

289

lower diversity32,33, and obesity can also result in reduced gut microbial diversity34.

290

PCA plots showed that rats clustered into relatively distinct groups based on different

291

types of edible oils (Figure 1A). This suggests that different types of edible oils 12


Page 12 of 36

Page 13 of 36


292

significantly altered the gut microbial populations. Figure 1E shows that at the phylum

293

level, the rat gut microbiota was dominated by Firmicutes and Bacteroidetes (together

294

accounting for approximately 90%). However, the Firmicutes/Bacteroidetes (F/B)

295

proportion in CO-treated rats was 1.02, which was higher than that of the OO (0.62)

296

and SO (0.60) groups. Chae et al.35 showed that lactulose as a prebiotic can increase

297

Firmicutes and the F/B ratio. A previous study pointed out that an increase in the F/B

298

ratio is beneficial in increasing the production of short-chain fatty acids of the

299

intestines and reducing the infection risk36, but also in terms of weight gain37.

300

In addition, CO-treated rats increased the Bacillus and Clostridia families in the

301

Firmicutes. Clostridia is a common symbiotic bacteria in the intestine, which shows

302

mutual benefits with the host and other microorganisms of the intestinal tract.38

303

Clostridia plays an important role in the intestinal tract, such as in releasing butyric

304

acid, reducing inflammatory responses, regulating immunity, and stimulating

305

regulatory T cell differentiation and accumulation.39,40 CO-treated rats exhibited an

306

increase in the phylum Actinobacteria (Figure 1E). The intake of a prebiotic can

307

stimulate the growth of probiotics such as the Actinobacteria.41,42 In addition, the

308

Bifidobacteriales and Coriobacteriales are the most widely studied of the

309

Actinobacteria. The Bifidobacteriales benefits human health, and several of these taxa

310

have been used in commercial probiotics. A reduction in the Bifidobacteriales is

311

associated with several human diseases, including a vitamin K deficiency, ectopic

312

disease, amnesia, and autism.43

313

A cladogram generated from the LEfSe analysis showed the most differentially

314

abundant taxa enriched in the gut microbiota of CO-treated rats and SO-treated rats

315

(Figure 2A), and CO-treated rats and OO-treated rats (Figure 2B). The results show

316

that the genus Bifidobacterium in CO-treated rats was significantly increased

317

compared to those in SO-treated rats and OO-treated rats. Monteagudo-Mera et al.43 13



318

showed that the intake of a prebiotic can stimulate the relative abundance of

319

Bifidobacterium in the gut of mice. In addition, Patterson et al.44 showed that dietary

320

omega-3 fatty acids (e.g., fish oil) can increase the genus Bifidobacterium in the

321

intestines. Caesar et al.30 pointed out that compared to lard oil, fish oil can increase the

322

genus Bifidobacterium in the intestinal tract of mice. Bifidobacterium is one of the

323

most important probiotics45, which promotes host health by stimulating the immune

324

system and vitamin synthesis, and inhibiting pathogen growth.46 Bifidobacterium also

325

affects the metabolism of cholesterol and lipids and is positively correlated with the

326

high-density lipoprotein (HDL) content.47 In addition, our previous study16 showed that

327

CO contained higher total phenolic content (13.4 mg/g of camellia oil), α-tocopherol (209

328

µg/g of camellia oil), and catechin (1.4 µg/g of camellia oil) than olive oil, indicating that

329

CO has higher antioxidants than OO (8.5 mg of total phenolic content/g, 61.0 µg of α-

330

tocopherol/g, and 0 µg of catechin/g). However, most polyphenols are not absorbed by the

331

upper GI tract, so the intestine contains a large amount of unabsorbed phenolics for use

332

by intestinal microbes.48 In addition, the catechin can significantly enhance the genus

333

Bifidobacterium in the human intestines.49 In addition to Bifidobacterium, CO

334

increases the relative abundances of other genera compared to SO, including

335

Collinsella and Bacteroides. Collinesella is associated to bile acid deconjugation, so its

336

relative abundance is proportional to plasma cholesterol concentrations.50 Kassinen et

337

al.51 pointed out that IBD patients had markedly reduced intestinal Collinesella and

338

Bacteroides populations. Moreover, Bacteroides can produce polysaccharide A, which

339

induces the growth of regulatory T cells and the secretion of cytokines to protect

340

against or prevent colitis.52,53 Marcobal et al.54 showed that human milk

341

oligosaccharides can promote the genera Bacteroides and Bifidobacterium.

342

SO- and OO-treated rats can significantly increase the relative abundance of

343

Prevotella compared to CO-treated rats (Figure 2A, B). Prevotella is a symbiotic in 14


Page 14 of 36

Page 15 of 36


344

the human intestines that degrades plant polysaccharides55 and synthesizes vitamin B1

345

to reduce the incidence of autism56. Kang et al.55 showed that autistic patients had

346

significantly decreased populations of Prevotella. A high-carbohydrate diet results in

347

higher Prevotella.57 The results of SO-treated rats were similar to those in animals with

348

diets high in simple carbohydrates that have higher levels of Prevotella and lower

349

levels of Bacteroides.57 Figure 2B shows that OO-treated rats had significantly

350

increased populations of the Pasteurellaceae compared to CO-treated rats. CD patients

351

have increased Pasteurellaceae.33 In addition, CO-treated rats also had increased

352

intestinal bacteria such as Adlercreutzia, Coriobacteriaceae, Christenesenellaceae, and

353

Blautia products compared to SO-treated rats (Figure 2A). Caesar et al.30 showed that

354

fish oil-treated mice contained higher Adlercreutzia than lard oil-treated mice. The

355

Coriobacteriaceae is closely associated with the metabolism of triglycerides and

356

cholesterol.58 Stenman et al.59 pointed out that leaner individuals have a higher relative

357

abundance of the Christenesenellaceae than those who are overweight and

358

metabolically unhealthy. Plant lignin secoisolariciresinol diglucoside can be converted

359

to enterodiol and enterolactone by Blautia producta, which can reduce the number and

360

size of tumors, and cell proliferation, and promote tumor cell apoptosis.60 As shown in

361

Figure 2B, CO-treated rats also had an increase in the genus Turicibacter compared to

362

OO-treated rats (Figure 2B). Turicibacter was negatively correlated with body weight,

363

and a thus high-fat diet reduces its relative abundance.61 Overall, our results

364

demonstrated that CO is capable of modulating the gut microbiome resulting in

365

enhancing the richness and diversity of the gut microbiota.

366

The gut microbial community is related to many disease pathologies, including

367

obesity, metabolic syndrome, diabetes, IBD, irritable bowel syndrome (IBS), and

368

celiac disease.62 An animal model of acetic acid-induced colitis resembles human

369

colitis with regard to the pathogenesis, histopathological characteristics, and 15



370

inflammatory mediator profile; thus, it is a beneficial tool for the screening of

371

therapeutic treatments for colitis.9 In this study, pretreatment with CO for 20 days

372

significantly modified the composition of the gut microbiota, and then CO also

373

improved erosion of the surface epithelium, hemorrhaging, edema, and acute

374

inflammation of the wall of the colon compared to those in the acetic acid-alone group

375

(p < 0.05) (Figure 4, Table 1). In addition, pretreatment with CO remarkably reduced

376

the MDA and MPO levels (p < 0.05), and slightly increased SOD and GSH in the

377

colon compared to those in the acetic acid-alone group (Figure 5). Oxidative damage

378

of colitis imbalances catalytic activity resulting in inflammation and oxidative damage

379

to the colon.63 SOD and GSH were significantly increased in CO-treated rats, which

380

may be attributed to decreased reactive oxygen species (ROS). CO possesses

381

flavonoids16 that block the arachidonic acid pathway and inhibit mechanisms of MPO

382

and MDA, thus inducing anti-inflammatory and antioxidative properties64. Earlier

383

workers16 also reported that CO elevates the antioxidant defense system such as SOD,

384

catalase, GSH, glutathione peroxidase, and GRd, suppresses lipid peroxidation, and

385

inhibits proinflammatory protein production in ethanol-induced gastric mucosal

386

damage in BALB/c mice. Our current results indicated that 2 mL/kg BW of CO had a

387

better ability to recover impairment of the antioxidant system induced by acetic acid

388

compared to OO and SO, which may have been due to CO modifying the composition

389

of the gut microbiota and CO being a rich source of squalene, vitamin E, and

390

flavonoids15. Consistent with these results, H&E staining showed acetic acid-induced

391

erosion of the surface epithelium, hemorrhaging, edema, and acute inflammation of the

392

colon wall. Indeed, histological data confirmed that camellia oil had a beneficial effect

393

against acetic acid-induced colitis, suggesting that it may be related to the decrease in

394

oxidative stress.

16


Page 16 of 36

Page 17 of 36


395

In conclusion, CO has the potential to modulate the gut microbiota and increase

396

the diversity of the gut microbiota, thereby ameliorating colitis as evidenced by the

397

significant reduction in lipid peroxidation, and increases in the antioxidant defense

398

system. The findings of the present study demonstrated that pretreatment with CO

399

improved acetic acid-induced colitis in a rat model. Therefore, it is suggested that

400

camellia oil might be useful in the protection against ulcerative colitis.

401

402

Acknowledgements

403

This research work was supported in part by the Council of Agriculture, Taiwan, under

404

grants 105AS-15.3.1-FD-Z1(4) and 106AS-14.3.1-FD-Z2(3). The authors thank Dr. J.

405

W. Liao of the Graduate Institute of Veterinary Pathobiology, National Chung Hsing

406

University for his assistance on the evaluation of pathological histology.

407 408

Conflict of Interest Statement

409

The authors declare that there are no conflicts of interest.

410 411

Abbreviations:

412

CD, Crohn's disease; CO, camellia oil; F/B, Firmicutes/Bacteroidetes; GSH,

413

glutathione; IBD, inflammatory bowel disease; IBS, irritable bowel syndrome; LDA,

414

linear discriminant analysis; LEfSe, LDA effect size; MDA, malondialdehyde; MPO,

415

myeloperoxidase; OO, olive oil; OTU, operational taxonomic units; PCA, principal

416

component analysis; PCR, polymerase chain reaction; SO, soybean oil; SOD,

417

superoxide dismutase; UC, ulcerative colitis.

418

17



419

REFERENCES

420

(1) Bindels, L. B.; Neyrinck, A. M.; Claus, S. P.; Le Roy, C. I.; Grangette, C.; Pot, B.;

421

Martinez, I.; Walter, J.; Cani, P. D.; Delzenne, N. M. Synbiotic approach restores

422

intestinal homeostasis and prolongs survival in leukaemic mice with cachexia.

423

MISME J. 2016, 10, 1456–1470.

424 425 426 427

(2) Schwabe, R. F.; Jobin, C. The microbiome and cancer. Nat. Rev. Cancer 2013, 13, 800–812. (3) Tilg, H.; Moschen, A. R. Microbiota and diabetes: an evolving relationship. Gut 2014, 63, 1513–1521.

428

(4) Bindels, L. B.; Delzenne, N. M.; Cani, P. D.; Walter, J. Towards a more

429

comprehensive concept for prebiotics. Nat. Rev. Gastroenterol. Hepatol. 2015, 12,

430

303–310.

431 432 433 434

(5) Scott, K. P.; Gratz, S. W.; Sheridan, P. O.; Flint, H. J.; Duncan, S. H. The influence of diet on the gut microbiota. Pharmacol. Res. 2013, 69, 52–60. (6) Tremaroli, V.; Ba¨ ckhed, F. Functional interactions betwe,en the gut microbiota and host metabolism. Nature 2012, 489, 242–249.

435

(7) Molodecky, N. A.; Soon, I. S.; Rabi, D. M.; Ghali, W. A.; Ferris, M.; Chernoff, G.;

436

Benchimol, E. I.; Panaccione, R.; Ghosh, S.; Barkema, H. W.; Kaplan, G. G.

437

Increasing incidence and prevalence of the inflammatory bowel diseases with time,

438

based on systematic review. Gastroenterology 2012, 142, 46–54.

439 440

(8) Karp, S. M.; Koch, T. R. Oxidative stress and antioxidants in inflammatory bowel disease. Dis. Mon. 2006, 52, 199–207.

441

(9) Randhawa, P. K.; Singh, K.; Singh, N.; Jaggi, A. S. A review on chemical-induced

442

inflammatory bowel disease models in rodents. Korean J. Physiol. Pharmacol.

443

2014, 18, 279–288. 18


Page 18 of 36

Page 19 of 36


444

(10) Kuralay, F.; Yildiz, C.; Ozutemiz, O.; Islekel, H.; Caliskan, S.; Bingol, B.; Ozkal,

445

S. Effects of trimetazidine on acetic acid-induced colitis in female Swiss rats. J.

446

Toxicol. Environ. Health. A 2003, 66, 169–179.

447

(11) Liu, S. P.; Dong, W. G.; Wu, D. F.; Luo, H. S.; Yu, J. P. Protective effect of

448

angelica sinensis polysaccharide on experimental immunological colon injury in

449

rats. World J. Gastroenterol. 2003, 9, 2786–2790.

450

(12) Ademoglu, E.; Erbil, Y.; Tam, B.; Barbaros, U.; Ilhan, E.; Olgac, V.; Mutlu-

451

Turkoglu, U. Do vitamin E and selenium have beneficial effects on

452

trinitrobenzenesulfonic acid-induced experimental colitis. Dig. Dis. Sci. 2004, 49,

453

102–108.

454

(13) Triantafillidis, J. K.; Merikas, E.; Georgopoulos, F. Current and emerging drugs

455

for the treatment of inflammatory bowel disease. Drug Des. Devel. Ther. 2011, 5,

456

185–210.

457

(14) Vecchi Brumatti, L.; Marcuzzi, A.; Tricarico, P. M.; Zanin, V.; Girardelli, M.;

458

Bianco, A. M. Curcumin and inflammatory bowel disease: potential and limits of

459

innovative treatments. Molecules 2014, 19, 21127–21153.

460

(15) Xiao, X.; He, L.; Chen, Y.; Wu, L.; Wang, Lin.; Liu, Z. Anti-inflammatory and

461

antioxidative effects of Camellia oleifera Abel components. Future Med. Chem.

462

2017, 9(17), doi.org/10.4155/fmc-2017-0109.

463

(16) Tu, P. S.; Tung, Y. T.; Lee, W. T.; Yen, G. C. Protective effect of camellia oil

464

(Camellia oleifera Abel.) against ethanol-induced acute oxidative injury of the

465

gastric mucosa in mice. J. Agric. Food Chem. 2017, 21, 4932–4941.

466

(17) Cheng, Y. T.; Wu, S. L.; Ho, C. Y.; Huang, S. M.; Cheng, C. L.; Yen, G. C.

467

Beneficial effects of camellia oil (Camellia oleifera Abel.) on ketoprofen-induced

468

gastrointestinal mucosal damage through upregulation of HO-1 and VEGF. J. 19



469 470 471

Agric. Food Chem. 2014, 62, 642–650. (18) Robert, C. Search and clustering orders of magnitude faster than BLAST. Bioinformatics 2010, 26, 2460–2461.

472

(19) Schloss, P. D.; Westcott, S. L.; Ryabin, T.; Hall, J. R.; Hartmann, M.; Hollister, E.

473

B.; Lesniewski, R. A.; Oakley, B. B.; Parks, D. H.; Robinson, C. J.; Sahl, J. W.;

474

Stres, B.; Thallinger, G. G.; Van Horn, D. J.; Weber, C. F. Introducing mothur:

475

open-source, platform-independent, community-supported software for describing

476

and comparing microbial communities”. Appl. Environ. Microbiol. 2009, 75,

477

7537–7541.

478 479

(20) Edgar, R. C. UPARSE: highly accurate OTU sequences from microbial amplicon reads. Nat. Meth. 2013, 10, 996–998.

480

(21) Quast, C.; Pruesse, E.; Yilmaz, P.; Gerken, J.; Schweer, T.; Yarza, P.; Peplies, J.;

481

Glöckner, F. O. The SILVA ribosomal RNA gene database project: improved data

482

processing and web-based tools. Nucleic Acids Res. 2013, 41, D590–D596.

483 484 485 486

(22) McMurdie, P. J.; Holmes, S. phyloseq: an R package for reproducible interactive analysis and graphics of microbiome census data. PLoS One 2013, 8, 1–11. (23) Dray, S.; Dufour, A. B. The ade4 package: implementing the duality diagram for ecologists. J. Stat. Soft. 2007, 22, 1–20.

487

(24) Lee, C. P.; Shih, P. H.; Hsu, C. L.; Yen, G. C. Hepatoprotection of tea seed oil

488

(Camellia oleifera Abel.) against CCl4-induced oxidative damage in rats. Food

489

Chem. Toxicol. 2007, 45, 888–895.

490

(25) Mannasaheb, B. A. A.; Kulkarni, P. V.; Sangreskopp, M. A.; Savant, C.; Mohan, A.

491

Protective effect of Agave americana Linn: leaf extract in acetic acidinduced

492

ulcerative colitis in rats. Ayu. 2015, 36, 101–106.

493

(26) Zheng, L.; Gao, Z. Q.; Wang, S. X. A chronic ulcerative colitis model in rats. 20


Page 20 of 36

Page 21 of 36


494

World J. Gastroenterol. 2000, 6, 150–152.

495

(27) Krawisz, J. E.; Sharon, P.; Stenson, W. F. Quantitative assay for acute intestinal

496

inflammation based on myeloperoxidase activity. Assessment of inflammation in

497

rat and hamster models. Gastroenterology 1984, 87, 1344–1350.

498

(28) Ohland, C. L.; Kish, L.; Bell, H.; Thiesen, A.; Hotte, N.; Pankiv, E.; Madsen, K. L.

499

Effects of Lactobacillus helveticus on murine behavior are dependent on diet and

500

genotype

501

Psychoneuroendocrinology 2013, 38, 1738–1747.

and

correlate

with

alterations

in

the

gut

microbiome.

502

(29) Monteagudo-Mera, A.; Arthur, J. C.; Jobin, C.; Keku, T.; Bruno-Barcena, J. M.;

503

Azcarate-Peril, M. A. High purity galacto-oligosaccharides enhance specific

504

Bifidobacterium species and their metabolic activity in the mouse gut microbiome.

505

Benef. Microbes. 2016, 7, 247–264.

506

(30) Caesar, R.; Tremaroli, V.; Kovatcheva-Datchary, P.; Cani, P. D.; Bäckhed, F.

507

Crosstalk between gut microbiota and dietary lipids aggravates WAT inflammation

508

through TLR signaling. Cell metabolism 2015, 22, 658–668.

509

(31) Ou, J. Y.; Huang, J. Q.; Song, Y.; Yao, S. W.; Peng, X. C.; Wang, M. F.; Ou, S. Y.,

510

Feruloylated oligosaccharides from maize bran modulated the gut microbiota in

511

rats. Plant Foods Hum. Nutr. 2016, 71, 123–128.

512

(32) Qin, J.; Li, R.; Raes, J.; Arumugam, M.; Burgdorf, K. S.; Manichanh, C.; Nielsen,

513

T.; Pons, N.; Levenez, F.; Yamada, T.; Mende, D. R.; Li, J.; Xu, J.; Li, S.; Li, D.;

514

Cao, J.; Wang, B.; Liang, H.; Zheng, H.; Xie, Y.; Tap, J.; Lepage, P.; Bertalan, M.;

515

Batto, J. M.; Hansen, T.; Le Paslier, D.; Linneberg, A.; Nielsen, H. B.; Pelletier,

516

E.; Renault, P.; Sicheritz-Ponten, T.; Turner, K.; Zhu, H.; Yu, C.; Li, S.; Jian, M.;

517

Zhou, Y.; Li, Y.; Zhang, X.; Li, S.; Qin, N.; Yang, H.; Wang, J.; Brunak, S.; Dore,

518

J.; Guarner, F.; Kristiansen, K.; Pedersen, O.; Parkhill, J.; Weissenbach, J.; Meta,

519

H. I. T. C.; Bork, P.; Ehrlich, S. D.; Wang, J. A human gut microbial gene 21



520

catalogue established by metagenomic sequencing. Nature 2010, 464, 59–65.

521

(33) Shreiner, A. B.; Kao, J. Y.; Young, V. B. The gut microbiome in health and in

522

disease. Curr. Opin. Gastroenterol. 2015, 31, 69–75.

523

(34) Turnbaugh, P. J.; Hamady, M.; Yatsunenko, T.; Cantarel, B. L.; Duncan, A.; Ley,

524

R. E.; Sogin, M. L.; Jones, W. J.; Roe, B. A.; Affourtit, J. P.; Egholm, M.;

525

Henrissat, B.; Heath, A. C.; Knight, R.; Gordon, J. I. A core gut microbiome in

526

obese and lean twins. Nature 2009, 457, 480–484.

527

(35) Chae, J. P.; Pajarillo, E. A. B.; Oh, J. K.; Kim, H.; Kang, D. K. Revealing the

528

combined effects of lactulose and probiotic enterococci on the swine faecal

529

microbiota using 454 pyrosequencing. Microb. Biotechnol. 2016, 9, 486–495.

530

(36) Molist, F.; Manzanilla, E. G.; Perez, J. F.; Nyachoti, C. M. Coarse, but not finely

531

ground, dietary fibre increases intestinal Firmicutes:Bacteroidetes ratio and

532

reduces diarrhoea induced by experimental infection in piglets. Br. J. Nutr. 2012,

533

108, 9–15.

534

(37) De Filippo, C.; Cavalieri, D.; Di Paola, M.; Ramazzotti, M.; Poullet, J. B.;

535

Massart, S.; Collini, S.; Pieraccini, G.; Lionetti, P. Impact of diet in shaping gut

536

microbiota revealed by a comparative study in children from Europe and rural

537

Africa. Proc. Natl. Acad. Sci. U S A 2010, 107, 14691–14696.

538

(38) Lopetuso, L. R.; Scaldaferri, F.; Petito, V.; Gasbarrini, A. Commensal Clostridia:

539

leading players in the maintenance of gut homeostasis. Gut pathog. 2013, 5, 23.

540

(39) Pryde, S. E.; Duncan, S. H.; Hold, G. L.; Stewart, C. S.; Flint, H. J. The

541

microbiology of butyrate formation in the human colon. FEMS Microbiol. Lett.

542

2002, 217, 133–139.

543

(40) Atarashi, K.; Tanoue, T.; Shima, T.; Imaoka, A.; Kuwahara, T.; Momose, Y.;

544

Cheng, G.; Yamasaki, S.; Saito, T.; Ohba, Y. Induction of colonic regulatory T cells

545

by indigenous Clostridium species. Science 2011, 331, 337–341.

546

(41) Martínez, I.; Kim, J.; Duffy, P. R.; Schlegel, V. L.; Walter, J. Resistant starches

547

types 2 and 4 have differential effects on the composition of the fecal microbiota

548

in human subjects. PLoS One 2010, 5, e15046. 22


Page 22 of 36

Page 23 of 36


549

(42) Barczynska, R.; Slizewska, K.; Litwin, M.; Szalecki, M.; Kapusniak, J. Effects of

550

dietary fiber preparations made from maize starch on the growth and activity of

551

selected bacteria from the Firmicutes, Bacteroidetes, and Actinobacteria phyla in

552

fecal samples from obese children. Acta. Biochim. Pol. 2016, 63, 261–266.

553

(43) Rajilić–Stojanović, M.; Biagi, E.; Heilig, H. G.; Kajander, K.; Kekkonen, R. A.;

554

Tims, S.; de Vos, W. M. Global and deep molecular analysis of microbiota

555

signatures in fecal samples from patients with irritable bowel syndrome.

556

Gastroenterology 2011, 141, 1792–1801.

557

(44) Patterson, E.; RM, O. D.; Murphy, E. F.; Wall, R.; O, O. S.; Nilaweera, K.;

558

Fitzgerald, G. F.; Cotter, P. D.; Ross, R. P.; Stanton, C. Impact of dietary fatty acids

559

on metabolic activity and host intestinal microbiota composition in C57BL/6J

560

mice. Br. J. Nutr. 2014, 111, 1905–1917.

561

(45) Pinto, S. S.; Fritzen-Freire, C. B.; Benedetti, S.; Murakami, F. S.; Petrus, J. C. C.;

562

Prudêncio, E. S.; Amboni, R. D. Potential use of whey concentrate and prebiotics

563

as carrier agents to protect Bifidobacterium-BB-12 microencapsulated by spray

564

drying. Food Res. Int. 2015, 67, 400–408.

565 566

(46) Rajilić-Stojanović, M. Function of the microbiota. Best Pract. Res. Clin. Gastroenterol. 2013, 27, 5–16.

567

(47) Martinez, I.; Wallace, G.; Zhang, C.; Legge, R.; Benson, A. K.; Carr, T. P.;

568

Moriyama, E. N.; Walter, J. Diet-induced metabolic improvements in a hamster

569

model of hypercholesterolemia are strongly linked to alterations of the gut

570

microbiota. Appl. Environ. Microbiol. 2009, 75, 4175–4184.

571

(48) Lee, H. C.; Jenner, A. M.; Low, C. S.; Lee, Y. K. Effect of tea phenolics and their

572

aromatic fecal bacterial metabolites on intestinal microbiota. Res. Microbiol. 2006,

573

157, 876–884.

574

(49) Tzounis, X.; Vulevic, J.; Kuhnle, G. G.; George, T.; Leonczak, J.; Gibson, G. R.;

575

Kwik-Uribe, C.; Spencer, J. P. Flavanol monomer-induced changes to the human

576

faecal microflora. Br. J. Nutr. 2008, 99, 782–792.

577

(50) Lahti, L.; Salonen, A.; Kekkonen, R. A.; Salojärvi, J.; Jalanka-Tuovinen, J.; Palva, 23



578

A.; Orešič, M.; de Vos, W. M. Associations between the human intestinal

579

microbiota, Lactobacillus rhamnosus GG and serum lipids indicated by integrated

580

analysis of high-throughput profiling data. PeerJ 2013, 1, e32.

581

(51) Kassinen, A.; Krogius-Kurikka, L.; Mäkivuokko, H.; Rinttilä, T.; Paulin, L.;

582

Corander, J.; Malinen, E.; Apajalahti, J.; Palva, A. The fecal microbiota of irritable

583

bowel syndrome patients differs significantly from that of healthy subjects.

584

Gastroenterology 2007, 133, 24–33.

585

(52) Round, J. L.; Lee, S. M.; Li, J.; Tran, G.; Jabri, B.; Chatila, T. A.; Mazmanian, S.

586

K. The Toll-like receptor 2 pathway establishes colonization by a commensal of

587

the human microbiota. Science 2011, 332, 974–977.

588 589

(53) Zhou, Y.; Zhi, F. Lower level of bacteroides in the gut microbiota is associated with inflammatory bowel disease: a meta-analysis. Biomed. Res. Int. 2016, 2016.

590

(54) Marcobal, A.; Barboza, M.; Sonnenburg, E. D.; Pudlo, N.; Martens, E. C.; Desai,

591

P.; Lebrilla, C. B.; Weimer, B. C.; Mills, D. A.; German, J. B. Bacteroides in the

592

infant gut consume milk oligosaccharides via mucus-utilization pathways. Cell

593

host microbe 2011, 10, 507–514.

594

(55) Kang, D. W.; Park, J. G.; Ilhan, Z. E.; Wallstrom, G.; LaBaer, J.; Adams, J. B.;

595

Krajmalnik-Brown, R. Reduced incidence of Prevotella and other fermenters in

596

intestinal microflora of autistic children. PLoS One 2013, 8, e68322.

597

(56) Arumugam, M.; Raes, J.; Pelletier, E.; Le Paslier, D.; Yamada, T.; Mende, D. R.;

598

Fernandes, G. R.; Tap, J.; Bruls, T.; Batto, J. M.; Bertalan, M.; Borruel, N.;

599

Casellas, F.; Fernandez, L.; Gautier, L.; Hansen, T.; Hattori, M.; Hayashi, T.;

600

Kleerebezem, M.; Kurokawa, K.; Leclerc, M.; Levenez, F.; Manichanh, C.;

601

Nielsen, H. B.; Nielsen, T.; Pons, N.; Poulain, J.; Qin, J.; Sicheritz-Ponten, T.;

602

Tims, S.; Torrents, D.; Ugarte, E.; Zoetendal, E. G.; Wang, J.; Guarner, F.;

603

Pedersen, O.; de Vos, W. M.; Brunak, S.; Dore, J.; Meta, H. I. T. C.; Antolin, M.;

604

Artiguenave, F.; Blottiere, H. M.; Almeida, M.; Brechot, C.; Cara, C.; Chervaux,

605

C.; Cultrone, A.; Delorme, C.; Denariaz, G.; Dervyn, R.; Foerstner, K. U.; Friss,

606

C.; van de Guchte, M.; Guedon, E.; Haimet, F.; Huber, W.; van Hylckama-Vlieg, 24


Page 24 of 36

Page 25 of 36


607

J.; Jamet, A.; Juste, C.; Kaci, G.; Knol, J.; Lakhdari, O.; Layec, S.; Le Roux, K.;

608

Maguin, E.; Merieux, A.; Melo Minardi, R.; M'Rini, C.; Muller, J.; Oozeer, R.;

609

Parkhill, J.; Renault, P.; Rescigno, M.; Sanchez, N.; Sunagawa, S.; Torrejon, A.;

610

Turner, K.; Vandemeulebrouck, G.; Varela, E.; Winogradsky, Y.; Zeller, G.;

611

Weissenbach, J.; Ehrlich, S. D.; Bork, P. Enterotypes of the human gut

612

microbiome. Nature 2011, 473, 174–180.

613 614

(57) Wu, G. D.; Bushmanc, F. D.; Lewis, J. D. Diet, the human gut microbiota, and IBD. Anaerobe 2013, 24, 117–120.

615

(58) Claus, S. P.; Ellero, S. L.; Berger, B.; Krause, L.; Bruttin, A.; Molina, J.; Paris, A.;

616

Want, E. J.; de Waziers, I.; Cloarec, O.; Richards, S. E.; Wang, Y.; Dumas, M. E.;

617

Ross, A.; Rezzi, S.; Kochhar, S.; Van Bladeren, P.; Lindon, J. C.; Holmes, E.;

618

Nicholson, J. K. Colonization-induced host-gut microbial metabolic interaction.

619

MBio. 2011, 2, e00271–00210.

620

(59) Stenman, L.; Burcelin, R.; Lahtinen, S. Establishing a causal link between gut

621

microbes, body weight gain and glucose metabolism in humans–towards treatment

622

with probiotics. Benef. Microbes 2016, 7, 11–22.

623

(60) Cardona, F.; Andrés-Lacueva, C.; Tulipani, S.; Tinahones, F. J.; Queipo-Ortuño,

624

M. I. Benefits of polyphenols on gut microbiota and implications in human health.

625

The J. Nutr. Biochem. 2013, 24, 1415–1422.

626

(61) Guo, X.; Li, J.; Tang, R.; Zhang, G.; Zeng, H.; Wood, R. J.; Liu, Z. High fat diet

627

alters gut microbiota and the expression of paneth cell-antimicrobial peptides

628

preceding changes of circulating inflammatory cytokines. Mediators Inflamm.

629 630

2017, 2017. (62) Brown, K.; DeCoffe, D.; Molcan, E.; Gibson, D. L. Diet-induced dysbiosis of the

631

intestinal microbiota and the effects on immunity and disease. Nutrients 2012, 4,

632

1095–1119.

633 634

(63) Circu, M. L.; Aw, T. Y. Intestinal redox biology and oxidative stress. Semin. Cell Dev. Biol. 2012, 23, 729–737. 25



635

(64) Tanideh, N.; Jamshidzadeh, A.; Sepehrimanesh, M.; Hosseinzadeh, M.; Koohi-

636

Hosseinabadi, O.; Najibi, A.; Raam, M.; Daneshi, S.; Asadi-Yousefabad, S. L.

637

Healing acceleration of acetic acid-induced colitis by marigold (Calendula

638

officinalis) in male rats. Saudi. J. Gastroenterol. 2016, 22, 50–56.

639

26


Page 26 of 36

Page 27 of 36


640

Figure legends

641

Figure 1. (A) Principal coordinate analysis (PCA) of the gut microbiota composition

642

in SD rats fed different oils. Based on the Bray-Curtis distance measure of all samples

643

of operational taxonomic unit (OTU)-level relative abundance profiles. (B-D) Alpha-

644

diversity indexes of the gut microbiota composition in SD rats fed different oils. The

645

boxplot demonstrates a distribution summary of diversity indices estimated at the OTU

646

level. (E) Effects of different edible oils on gut phylum-level microbiota composition

647

of SD rats. Only phyla with top five average abundances were included, with other

648

phyla collapsed into “Others”. Animals received oral administration of 2 mL/kg of

649

soybean oil (SO), camellia oil (CO), or olive oil (OO) for 20 days.

650 651

Figure 2. Effects of (A) camellia oil (CO) and soybean oil (SO) and (B) camellia oil

652

and olive oil (OO) on the gut microbiota composition of SD rats at the phylum level.

653

Cladogram generated from the linear discriminant analysis effect size (LEfSe)

654

analysis, showing the most differentially abundant taxa enriched in the microbiota of

655

SD rats fed (A) CO (red) or SO (green) and (B) CO (red) or OO (green). Significantly

656

differential abundances in LEfSe comparisons, sorted by p values in ascending order.

657

Animals received oral administration of 2 mL/kg of SO or CO for 20 days.

658 659

Figure 3. Effect of camellia oil (CO) on (A) the exterior and (B) hemorrhage score in

660

the colon of acetic acid (AA)-induced colitis of SD rats. All treatments [soybean oil

661

(SO), CO, or olive oil (OO)] were given once a day for 24 consecutive days. Rats in the

662

acetic acid (AA)+sulfasalazine (SASP) group (a positive control) were orally

663

pretreated with SO for 24 days and were treated with 500 mg/kg body weight (BW)

664

SASP on days 21-24 for 4 days. Colitis was induced by the transrectal administration 27



665

of 2 mL of 4% AA once on day 21. The degree of lesions was graded from 1 to 5

666

depending on the severity: 1 = minimal (< 1%); 2 = slight (1%~25%); 3 = moderate

667

(26%~50%); 4 = moderate/severe (51%~75%); 5 = severe/high (76%~100%). Data are

668

expressed as the mean ± standard deviation of six mice. The letters indicate

669

statistically significant differences between groups (p < 0.05) by Duncan’s test.

670 671

Figure 4. Effect of camellia oil (CO) on histological slides in the colon of acetic acid

672

(AA)-induced colitis of SD rats. All treatments [soybean oil (SO), CO, or olive oil

673

(OO)] were given once a day for 24 consecutive days. Rats of the acetic acid

674

(AA0+sulfasalazine (SASP) group (a positive control) were orally pretreated with SO

675

for 24 days and were treated with 500 mg/kg body weight (BW) SASP on days 21-24

676

for 4 days. Colitis was induced by the transrectal administration of 2 mL of 4% AA

677

once on day 21. (A-C) Control group, (D-F) AA group, (G-I) AA+SASP group, (J-L)

678

AA+CO group, and (M-O) AA+CO group. A normal architecture of the colon was

679

found in the control group (A-C). Necrotizing colitis included focal, lost crypts, cryptic

680

regeneration, edema, and inflammatory cells, and fibroblast cell infiltration, ulceration,

681

and hemorrhage were noted in the mucosal and submucosal layers of the colon, and

682

colitis was graded as moderate/severe in the AA group (D-F), slight in the AA+SASP

683

group (G-I) and AA+CO group (J-L), and moderate in the AA+CO group (M-O). 20x

684

(A, D, G, J, and M), 40x (B, E, H, K, and N), 100x (C, F, I, L, and O). H&E stain.

685 686

Figure 5. Effects of camellia oil (CO) on the levels of (A) glutathione (GSH), (B)

687

superoxide dismutase (SOD), (C) thiobarbituric acid-reactive substances (TBARSs)

688

and malondialdehyde (MDA), and (D) myeloperoxidase (MPO) in the colon of SD rats

689

with acetic acid (AA)-induced ulcerative colitis. All treatments (SO, CO, or OO) were 28


Page 28 of 36

Page 29 of 36


690

given once a day for 24 consecutive days. Rats in the AA+SASP group were orally

691

pretreated with SO for 24 days and were treated with 500 mg/kg body weight (BW)

692

sulfasalazine (SASP) on days 21-24 for 4 days. Colitis was induced by the transrectal

693

administration of 2 mL of 4% AA once on day 21. Data are expressed as the mean ±

694

standard deviation of six mice. The letters indicate statistically significant differences

695

between groups (p < 0.05) by Duncan’s test.

29



Page 30 of 36

Table 1. Effect of camellia oil (CO) on histological slides in the colon of SD rats with acetic acid (AA)-induced ulcerative colitis Control

AA

AA+SASP

AA+CO

AA+OO

Colitis, necrotizing, general

0.00±0.00c

4.17±0.40a

2.00±0.73b

2.50±0.43b

3.00±0.37ab

Lost, crypt

0.00±0.00c

4.00±0.52a

1.67±0.80b

2.33±0.56b

3.00±0.37ab

Regeneration, 0.00±0.00c crypt

1.50±0.22ab

1.33±0.42b

1.67±0.42ab

2.33±0.21a

Edema, submucosal

0.00±0.00c

4.67±0.21a

2.67±0.92b

3.00±0.63b

3.83±0.31ab

Inflammation, mononuclear 0.00±0.00c cells

5.00±0.00a

2.67±0.92b

3.50±0.62ab

4.5±0.34a

Ulcers, with fibroblast cell 0.00±0.00c infiltration

4.00±0.52a

1.67±0.80b

2.33±0.56b

3.00±0.37ab

Hemorrhage, 0.00±0.00c focal

2.33±0.56a

1.17±0.54abc 0.67±0.42bc

0.00±0.00c

Total

1.67±0.42ab

25.67±1.48a 13.17±4.85b 16.00±3.31b 21.33±1.54ab

All treatments [soybean oil (SO), CO, or olive oil (OO)] were given once a day for 24 consecutive days. Rats of the acetic acid (AA)+sulfaslalzine (SASP) group (a positive control) were pretreated orally with SO for 24 days and were treated with 500 mg/kg body weight (BW) SASP on days 21-24 for 4 days. Colitis was induced by the transrectal administration of 2 mL of 4% AA once on day 21. The degree of lesions was graded from 1 to 5 depending on the severity: 1 = minimal (< 1%); 2 = slight (1%~25%); 3 = moderate (26%~50%); 4 = moderate/severe (51%~75%); 5 = severe/high (76%~100%). Data are expressed as the mean ± standard deviation of six a-c

mice. The letters indicate statistically significant differences between groups (p < 0.05) by Duncan’s test.

30


Page 31 of 36


Figure 1.

31



Figure 2.

32


Page 32 of 36

Page 33 of 36


Figure 3

33



Figure 4.

34


Page 34 of 36

Page 35 of 36


Figure 5

35



TOC Graphic

36


Page 36 of 36

Camellia Oil (Camellia oleifera Abel.) Modifies the Composition of Gut

Recommend Documents