A Limonoid 7-Deacetoxy-7-Oxogedunin from Andiroba, Carapa

(HFD)-fed mice. C57BL/6 mice were fed a low-fat diet or an HFD, and orally administered. 23. CG-1 (20 mg/kg) for 7 weeks. CG-1 lowered body weight gai...
0 downloads 0 Views 659KB Size
Subscriber access provided by Chalmers Library

Bioactive Constituents, Metabolites, and Functions

A Limonoid 7-Deacetoxy-7-Oxogedunin from Andiroba, Carapa guianensis, Meliaceae Decreased Body Weight Gain, Improved Insulin Sensitivity, and Activated Brown Adipose Tissue in High-fat Diet-fed Mice Chihiro Matsumoto, Toko Maehara, Reiko Tanaka, and Ko Fujimori J. Agric. Food Chem., Just Accepted Manuscript • DOI: 10.1021/acs.jafc.9b04362 • Publication Date (Web): 21 Aug 2019 Downloaded from pubs.acs.org on August 25, 2019

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 34

Journal of Agricultural and Food Chemistry

1

A Limonoid 7-Deacetoxy-7-Oxogedunin from Andiroba, Carapa guianensis,

2

Meliaceae Decreased Body Weight Gain, Improved Insulin Sensitivity, and

3

Activated Brown Adipose Tissue in High-fat Diet-fed Mice

4 5

Chihiro Matsumoto#, Toko Maehara#, Reiko Tanaka$, and Ko Fujimori#,*

6 7 8

# Department

Nasahara, Takatsuki, Osaka 569-1094, Japan

9 10 11

of Pathobiochemistry, Osaka University of Pharmaceutical Sciences, 4-20-1

$ Department

of Medicinal Chemistry, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan

12 13

* To whom correspondence should be addressed: Ko Fujimori, Ph.D.

14

Department of Pathobiochemistry, Osaka University of Pharmaceutical Sciences,

15

4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan

16

Phone and Fax: +81-72-690-1215, E-mail: [email protected]

1 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

ABSTRACT

18 19 20

We examined the anti-obesity effect of a limonoid 7-deacetoxy-7-oxogedunin, named CG-1

21

purified from the seeds of Carapa guianensis, Meliaceae, known as andiroba in high-fat diet

22

(HFD)-fed mice. C57BL/6 mice were fed a low-fat diet or an HFD, and orally administered

23

CG-1 (20 mg/kg) for 7 weeks. CG-1 lowered body weight gain and improved serum

24

triglyceride level and insulin sensitivity in HFD-fed mice. The expression level of the

25

adipogenesis-related genes was lowered by CG-1 in visceral white adipose tissue (vWAT).

26

The mRNA expression level of the macrophage-related genes decreased in vWAT following

27

administration of CG-1 to HFD-fed mice. Noteworthly, CG-1 activated brown adipose tissue

28

(BAT) with enhanced expression of uncoupling protein 1 and increased rectal temperature in

29

HFD-fed mice. These results indicate that a limonoid CG-1 decreased body weight gain and

30

ameliorated hypertriglyceridemia and insulin resistance with activation of BAT in HFD-fed

31

mice.

32 33 34

Keywords: andiroba, limonoid, insulin resistance, obesity, BAT

35

2 ACS Paragon Plus Environment

Page 2 of 34

Page 3 of 34

Journal of Agricultural and Food Chemistry

INTRODUCTION

37 38 39

Obesity is currently growing epidemic worldwide 1 and represents the complex interaction of

40

genetic, behavioral, and environmental effects 2. Obesity is closely related to the occurrence

41

of a variety of metabolic diseases such as hypertension, hyperlipidemia, type 2 diabetes

42

mellitus, and cardiovascular disease

43

chronic inflammation state through infiltrating and activating macrophages in obese adipose

44

tissue, which finally leads to insulin resistance and glucose intolerance 5-8.

45

1, 3, 4.

It is also known that obesity is associated with the

These are two different types of adipose tissue: white adipose tissue (WAT) that stores 9

46

energy as triglyceride (TG)

and brown adipose tissue (BAT) that burns energy for

47

thermogenesis 10. Adipogenesis in WAT is regulated via a coordinated transcription cascade 11.

48

Peroxisome proliferator-activated receptor (PPAR) γ, CCAAT/enhancer binding proteins

49

(C/EBPs), and Krüppel-like factors (KLFs) play key roles in the control of adipogenesis

50

through regulation of various adipogenesis-associated proteins. In contrast, BAT oxidizes

51

intracellular lipids to produce heat through the activation of the thermogenesis-related

52

proteins such as uncoupling protein 1 (UCP1) 10, 12. Thus, both adipose tissues play important

53

roles in the control of energy homeostasis.

54

Presently, overeating, especially intake of fats, is a critical problem worldwide, because

55

it promotes obesity and the occurrence of the obesity-triggered metabolic diseases. A variety

56

of therapeutic methods for the prevention and treatment of obesity such as diet modification,

57

exercise, surgery, and pharmacotherapy are now available 13. Although the pharmacotherapy

58

is more common, some synthetic medicines fail to produce the desired effects or show

59

unexpected side effects

60

natural products are used for treatment of obesity by preventing weight gain or promoting

14, 15.

Some traditional medicines and constituents derived from

3 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

Page 4 of 34

61

weight loss 16, 17. One of the clinical benefit of natural products is that the effects are generally

62

mild, but they show fewer side effects 17.

63

Limonoids are phytochemicals of the triterpenoids that are abundant in the Rutaceae

64

and Meliaceae plant families 18-20. Limonin and nomilin are limonoids and contained plenty in

65

citrus that is a member of the Rutaceae family

66

abilities such as anti-cancer, anti-malarial, and anti-microbial activities

67

several limonoids such as nomilin 21, obacunone 22, ceramicine B 23, and kihadanin B 24 have

68

anti-adipogenic or anti-obesity effects. However, there are few in vivo analyses of the

69

biological effects of limonoids on metabolic diseases.

18-20.

Limonoids have several biological 18-20.

Moreover,

70

Carapa guianensis known as andiroba is a large neotropical tree, belonging to the

71

Meliaceae family. Andiroba is grown in the north of South America, Central America,

72

Sub-Saharan Africa, and the Amazon region in Brazil 25, 26. The seed oil of C. guianensis has

73

been used as a natural medicine for treating allergies

74

Andiroba seeds contain abundant limonoids

75

CG-1 as the major limonoid 30. We recently found that a limonoid CG-1 has anti-adipogenic

76

effects in 3T3-L1 adipose cells 31. In the present study, we examined an anti-obesity effect of

77

a limonoid CG-1 of andiroba in high-fat diet (HFD) -fed obese mice.

29,

27,

cancer

28,

and inflammation

27.

including 7-deacetoxy-7-oxogedunin, named

78

4 ACS Paragon Plus Environment

Page 5 of 34

Journal of Agricultural and Food Chemistry

MATERIALS AND METHODS

80 81 82

Purification of A Limonoid CG-1 from Seeds of Andiroba

83

A limonoid CG-1 (Figure 1, inset) was purified from andiroba seeds in previous study

84

Prior to the initiation of this study, we confirmed the purity of CG-1 using HPLC (Figure 1;

85

JASCO, Tokyo, Japan) with acetonitrile:H2O (60:40) as the mobile phase and the

86

COSMOSIL 5C18-MS column (Nacalai Tesque, Kyoto, Japan). The purity of CG-1 was

87

calculated using a JASCO 807-IT integrator (JASCO). Furthermore, the chemical structure of

88

CG-1 was determined using nuclear magnetic resonance (data not shown).

32.

89 90

Animals

91

Mice (C57BL/6J, male, 6-week-old; Japan SLC, Shizuoka, Japan) were maintained in

92

temperature (24 °C)-

93

randomly divided into four groups [n=10 for each HFD group and n=10 for each low-fat diet

94

(LFD) group]. These groups were orally administered CG-1 (20 mg/kg) that was suspended in

95

0.5%(w/v) methyl cellulose 400 (FUJIFILM Wako Pure Chemicals, Osaka, Japan) or

96

0.5%(w/v) methyl cellulose 400 alone (vehicle), respectively, each other day. They were

97

designated as CG-1/LFD, CG-1/HFD, vehicle/LFD, and vehicle/HFD groups, respectively

98

(n=10). Each group was fed either an LFD (FR-2, 4.8% fat; Funabashi Farm, Chiba, Japan) or

99

HFD (D12492; 35% fat; Research Diet, New Brunswick, NJ, USA). The formulation of LFD

100

and HFD was shown in Supplemental Table 1. Body weight was measured once a week. The

101

mice were given free access to food and water. All animal studies were performed according

102

to the guideline of the Animal committee of Osaka University of Pharmaceutical Sciences.

and light (12 h light-12 h dark cycle)-controlled room. The mice were

103

5 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

Page 6 of 34

104

Measurement of mRNA Expression Level

105

RNA extraction of and first-strand cDNA synthesis were done as described previously

106

Messenger RNA levels were measured using quantitative PCR (qPCR) using Power SYBR

107

Green PCR Master Mix (Thermo Fischer Scientific, Waltham, MA, USA) and gene-specific

108

primers (Table 1) in an ABI 7500 Real-Time PCR System (Thermo Fischer Scientific), The

109

expression level was analyzed using the 2-ΔΔCt method and normalized to TATA-binding

110

protein (TBP) mRNA.

33.

111 112

Western Blot Analysis

113

Protein was isolated from tissues as described previously 34. A Pierce BCA Protein Assay Kit

114

(Thermo Fisher Scientific) was used to determine protein concentrations. Proteins were

115

separated on SDS-PAGE and transferred onto polyvinylidene fluoride membranes (Immobilon;

116

Merck Millipore, Whitehouse Station, NJ, USA). The membranes were then blocked using

117

Blocking One (Nacalai Tesque), and subsequently incubated with the following primary

118

antibodies: anti-uncoupling protein (UCP) 1 (U6382) and anti-glucose transporter (GLUT) 4

119

(G4048) polyclonal antibodies and anti-β-actin monoclonal antibody (AC-15; Sigma, St.

120

Louis, MO, USA), anti-CCAAT/enhancer-binding protein (C/EBP) α polyclonal antibody

121

(#2295; Cell Signaling, Danvers, MA, USA), anti-fatty acid synthase (FAS; H-300), and

122

anti-stearoyl-CoA desaturase (SCD) polyclonal antibodies (Santa Cruz Biotechnology, Dallas,

123

TX,

124

horseradish-peroxidase-conjugated secondary antibodies (Santa Cruz Biotech., Dallas, TX,

125

USA), immunoreactive signals were visualized by an ECL Prime Western Blotting Detection

126

Reagent (GE Healthcare, Buckinghamshire, UK) and an LAS-3000 Lumino Image Analyzer

127

(FUJIFILM, Tokyo, Japan), and analyzed using a Multi-Gauge software (FUJIFILM).

USA).

After

incubation

of

the

membranes

6 ACS Paragon Plus Environment

with

the

respective

Page 7 of 34

Journal of Agricultural and Food Chemistry

128 129

Serum Biochemical Parameter

130

Mice were fasted for 16 h, and blood samples were collected from the abdominal aorta.

131

Serum insulin, triglyceride (TG), glucose, total cholesterol (CHO), low-density lipoprotein

132

(LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and non-esterified fatty acid

133

(NEFA) levels were measured using the respective LBIS Mouse Insulin ELISA KIT (RTU;

134

FUJIFILM Wako Shibayagi, Gunma, Japan), L-Type TG M, GLUCOSE, CHO M, L-Type

135

LDL-C, L-Type HDL-C, and NEFA Kits (FUJIFILM Wako Pure Chemicals).

136 137

Insulin Tolerance Test (ITT)

138

Mice were fasted for 16 h, and then intraperitoneally injected HUMULIN® (0.75 IU/kg body

139

weight; Eli Lilly, Indianapolis, IN, USA). The measurement of glucose levels were carried

140

out using blood samples that prepared from tail vein at 0, 15, 30, 60, and 120 min after the

141

injection by the use of a MEDISAFE MINI Blood Glucose Monitoring System (Terumo,

142

Tokyo, Japan).

143 144

Oral Glucose Tolerance Test (OGTT)

145

Mice were fasted for 16 h before orally administrating glucose (2 g/kg body weight). Glucose

146

level in blood samples from the tail vein was measured with a MEDISAFE MINI Blood

147

Glucose Monitoring System (Terumo) at 0, 15, 30, 60, and 120 min after administration.

148

OGTT was carried out using the same mice as those used in ITT in different weeks.

149 150

Statistical Analysis

151

Dara were shown as means ± S.D. or S.E. Results were analyzed using one way ANOVA, and

7 ACS Paragon Plus Environment

Journal of Agricultural and Food Chemistry

152

significance was analyzed by Tukey’s test. p