ダイオキシン低用量曝露母体の肝薬物代謝酵素活性に対するシークワーサー由来ポリメトキシフラボノイド：ノビレチンのin vitro阻害効果

ドン酸代謝がある．アラキドン酸はω-6 多価不

飽和脂肪酸であり，シクロオキシゲナーゼ，リポ

1)

キシゲナーゼ，P450 によって代謝される．ラッ

トでの P450 による代謝には主に CYP2C11，2C6，

1A1 及び 1A2 が関係しており，エポキシ化また

2)

はヒドロキシ化によってエポキシエイコサトリエ

ン酸（EET）またはヒドロキシエイコサテトラエ

ン 酸（HETE）に 代 謝 さ れ る55)．CYP2C6 は

3)

mid-chain（m）HETE を 48.3％，EET を 29.4％

生成する55)．mHETE の中でも特に 12 位が水酸

化 さ れ た 12-HETE の 産 生 が 一 番 多 く，12HETE は炎症促進作用，アテローム性動脈硬化症

4)

の発生，腫瘍細胞のアポトーシスの抑制，血管新

生，増殖の促進などに関わっている56)~59)．この

ことから，CYP2C6 活性の増加は細胞へ悪影響を

5)

もたらす mHETE の産生につながり，ノビレチ

ンはその毒性に対する改善効果を示すことが予想

される．これまでに TCDD による HETE 量変動

への影響は HETE 種全体，18，19，20-HETE の

増加については検討されているが60)~62)，TCDD

6)

による 12-HETE の変動については未だ情報が不

十分である．そのため，CYP2C6 によるアラキド

ン酸代謝を介した毒性発現については，今後検討

の余地があると考えられる．

7)

TCDD 低用量曝露母体肝臓では多種の P450 に

（ 86 ）

Masuda Y : Behavior and toxic effects of PCBs

and PCDFs in Yusho patients for 35 years. J.

Dermatological Sci. 1 : S11-S20, 2005.

Furue M, Ishii Y, Tsukimori K and Tsuji G : Aryl

Hydrocarbon Receptor and Dioxin-Related

Health Hazards-Lessons from Yusho. Int. J. Mol.

Sci. 22 : 708, 2021.

Poland A and Knutson JC : 2,3,7,8-tetrachlorodibenzo-p-dioxin and related halogenated

aromatic hydrocarbons : examination of the

mechanism of toxicity. Ann. Rev. Pharmacol.

Toxicol. 26 : 517-554, 1982.

Hankinson O : The aryl hydrocarbon receptor

complex. Annu. Rev. Pharmacol. Toxicol. 35 :

307-340, 1995.

Mutoh J, Taketoh J, Okamura K, Kagawa T,

Ishida T, Ishii Y and Yamada H : Fetal pituitary

gonadotropin as an initial target of dioxin in its

impairment of cholesterol transportation and

steroidogenesis in rats. Endocrinology. 147 :

927-936, 2006.

Takeda T, Matsumoto Y, Koga T, Mutoh J,

Nishimura Y, Shimazoe T, Ishii Y, Ishida T and

Yamada H : Maternal exposure to dioxin

disrupts gonadotropin production in fetal rats

and imprints defects in sexual behavior. J.

Pharmacol. Exp. Ther. 329 : 1091-1099, 2009.

Takeda T, Fujii M, Taura J, Ishii Y and Yamada

H : Dioxin silences gonadotropin expression in

perinatal pups by inducing histone deacetylases : a new insight into the mechanism for the

ノビレチンによる in vitro P450 阻害効果

8)

9)

10)

11)

12)

13)

14)

15)

16)

imprinting of sexual immaturity by dioxin. J.

Biol. Chem. 287 : 18440-18450, 2012.

Hattori Y, Takeda T, Nakamura A, Nishida K,

Shioji Y, Fukumitsu H, Yamada H and Ishii Y :

The aryl hydrocarbon receptor is indispensable

for dioxin-induced defects in sexually-dimorphic behaviors due to the reduction in fetal

steroidogenesis of the pituitary-gonadal axis in

rats. Biochem. Pharmacol. 154 : 213-221, 2018.

Mably TA, Moore RW and Peterson RE : In

utero and lactational exposure of male rats to

2,3,7,8-tetrachlorodibenzo-p-dioxin. 1. Effects

on androgenic status. Toxicol. Appl. Pharmacol.

114 : 97-107, 1992.

Gray LE Jr and Ostby JS : In utero 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) alters reproductive morphology and function in female rat

offspring. Toxicol. Appl. Pharmacol. 133 : 285294, 1995.

Gray LE Jr, Ostby JS and Kelce WR : A doseresponse analysis of the reproductive effects of

a single gestational dose of 2,3,7,8-tetrachlorodibenzo-p-dioxin in male Long Evans Hooded

rat offspring. Toxicol. Appl. Pharmacol. 146 :

11-20, 1997.

Hurst CH, DeVito MJ, Setzer RW and Birnbaum

LS : Acute administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in pregnant Long

Evans rats : association of measured tissue

concentrations with developmental effects.

Toxicol. Sci. 53 : 411-420, 2000.

Kopf PG, Scott JA, Agbor LN, Boberg JR, Elased

KM, Huwe JK and Walker MK : Cytochrome

P4501A1 is required for vascular dysfunction

and hypertension induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin. Toxicol. Sci. 117 : 537546, 2010.

Denison MS, Soshilov AA, He G, DeGroot DE

and Zhao B : Exactly the same but different :

promiscuity and diversity in the molecular

mechanisms of action of the aryl hydrocarbon

(dioxin) receptor. Toxicol. Sci, 124 : 1-22, 2011.

Nebert DW, Roe AL, Dieter MZ, Solis WA, Yang

Y and Dalton TP : Role of the aromatic

hydrocarbon receptor and [Ah] gene battery in

the oxidative stress response, cell cycle control,

and apoptosis. Biochem. Pharmacol. 59 : 65-85,

2000.

Emi Y, Ikushiro S and Kato Y : Thyroxine-metabolizing rat uridine diphosphate-glucuronosyltransferase 1A7 is regulated by thyroid hormone receptor. Endocrinology. 148 : 6124-6133,

2007.

17)

18)

19)

20)

21)

22)

23)

24)

（ 87 ）

25)

26)

27)

145

Koga N, Matsuo M, Ohta C, Haraguchi K,

Matsuoka M, Kato Y, Ishii T, Yano M and Ohta

H : Comparative study on nobiletin metabolism

with liver microsomes from rats, Guinea pigs

and hamsters and rat cytochrome p450. Biol.

Pharm. Bull. 30 : 2317-2323, 2007.

Hattori Y, Takeda T, Fujii M, Taura J, Ishii Y

and Yamada H : Dioxin-induced fetal growth

retardation : the role of a preceding attenuation

in the circulating level of glucocorticoid. Endocrine. 47 : 572-580, 2014.

Lacroix MC, Guibourdenche J, Frendo JL,

Pidoux G and Evain-Brion D : Placental growth

hormones. Endocrine. 19 : 73-79, 2002.

Jesus KD, Wang X and Liu JL : A general IGF-I

overexpression effectively rescued somatic

growth and bone deficiency in mice caused by

growth hormone receptor knockout. Growth.

Factors. 27 : 438-447, 2009.

Porter TE : Regulation of pituitary somatotroph

differentiation by hormones of peripheral endocrine glands. Domest. Anim. Endocrinol. 29 :

52-62, 2005.

Nogami H and Hisano S : Functional maturation

of growth hormone cells in the anterior pituitary

gland of the fetus. Growth. Horm. IGF. Res. 18 :

379-388, 2008.

Vylitová M, Miksík I and Pácha J : Metabolism

of corticosterone in mammalian and avian

intestine. Gen. Comp. Endocrinol. 109 : 315-324,

1998.

Kucka M, Vagnerová K, Klusonová P, Miksík I

and Pácha J : Corticosterone metabolism in

chicken tissues : evidence for tissue-specific

distribution of steroid dehydrogenases. Gen.

Comp. Endocrinol. 147 : 377-383, 2006.

Watlington CO, Atkins JL, McNeil JS, Grogan

WM and Johnson JP : Corticosterone is converted to 6 beta-hydroxycorticosterone in rat :

effects of the metabolite on urinary electrolyte

excretion. J. Steroid. Biochem. 31 : 947-954,

1988.

Waxman DJ, Attisano C, Guengerich FP and

Lapenson DP : Human liver microsomal steroid

metabolism : identification of the major microsomal steroid hormone 6 beta-hydroxylase

cytochrome P-450 enzyme. Arch. Biochem.

Biophys. 263 : 424-436, 1988.

Negishi M, Uno T, Honkakoski P, Sueyoshi T,

Darden TA and Pedersen LP : The roles of

individual amino acids in altering substrate

specificity of the P450 2a4/2a5 enzymes.

Biochimie. 78 : 685-694, 1996.

146

佳乃子

28) Bentli R, Ciftci O, Cetin A, Unlu M, Basak N and

Cay M : Oral administration of hesperidin, a

citrus flavonone, in rats counteracts the oxidative stress, the inflammatory cytokine production, and the hepatotoxicity induced by the

ingestion of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Eur. Cytokine. Netw. 24 : 91-96,

2013.

29) Tan YQ, Chiu-Leung LC, Lin SM and Leung

LK : The citrus flavonone hesperetin attenuates

the nuclear translocation of aryl hydrocarbon

receptor. Comp. Biochem. Physiol. C. Toxicol.

Pharmacol. 210 : 57-64, 2018.

30) Suh KS, Choi EM, Kim HS, Park SY, Chin SO,

Rhee SY, Pak YK, Choe W, Ha J and Chon S :

Xanthohumol ameliorates 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced cellular toxicity in

cultured MC3T3-E1 osteoblastic cells. J. Appl.

Toxicol. 38 : 1036-1046, 2018.

31) Choi EM, Suh KS, Jung WW, Park SY, Chin SO,

Rhee SY, Pak YK and Chon S : Glabridin

attenuates antiadipogenic activity induced by

2,3,7,8-tetrachlorodibenzo-p-dioxin in murine

3T3-L1 adipocytes. J. Appl. Toxicol. 38 : 14261436, 2018.

32) Guo S, Qiu P, Xu G, Wu X, Dong P, Yang G,

Zheng J, McClements DJ and Xiao H : Synergistic anti-inflammatory effects of nobiletin and

sulforaphane in lipopolysaccharide-stimulated

RAW 264. 7 cells. J. Agric. Food. Chem. 60 :

2157-2164, 2012.

33) Wu X, Song M, Rakariyatham K, Zheng J, Guo S,

Tang Z, Zhou S and Xiao H : Anti-inflammatory

effects of 4ʼ-demethylnobiletin, a major metabolite of nobiletin. J. Funct. Foods. 19 : 278-287,

2015.

34) Nakajima A, Ohizumi Y and Yamada K :

Anti-dementia Activity of Nobiletin, a Citrus

Flavonoid : A Review of Animal Studies. Clin.

Psychopharmacol. Neurosci. 12 : 75-82, 2014.

35) Liu J, Wang S, Tian S, He Y, Lou H, Yang Z,

Kong Y and Cao X : Nobiletin inhibits breast

cancer via p38 mitogen-activated protein

kinase, nuclear transcription factor-kappaB, and

nuclear factor erythroid 2-related factor 2

pathways in MCF-7 cells. Food. Nutr. Res. 21 :

62, 2018.

36) Sp N, Kang DY, Kim DH, Park JH, Lee HG, Kim

HJ, Darvin P, Park YM and Yang YM : Nobiletin

inhibits CD36-dependent tumor angiogenesis,

migration, invasion, and sphere formation

through the Cd36/Stat3/Nf-Κ b signaling axis.

Nutrients. 10 : 772, 2018.

ほか６名

37)

38)

39)

40)

41)

（ 88 ）

42)

43)

44)

45)

46)

47)

He B, Nohara K, Park N, Park YS, Guillory B,

Zhao Z, Garcia JM, Koike N, Lee CC, Takahashi

JS, Yoo SH and Chen Z : The Small Molecule

Nobiletin Targets the Molecular Oscillator to

Enhance Circadian Rhythms and Protect

against Metabolic Syndrome. Cell. Metab. 23 :

610-621, 2016.

Lone J, Parray HA and Yun JW : Nobiletin

induces brown adipocyte-like phenotype and

ameliorates stress in 3T3-L1 adipocytes. Biochimie. 146 : 97-104, 2018.

Surichan S, Androutsopoulos VP, Sifakis S,

Koutala E, Tsatsakis A, Arroo RR and Boarder

MR : Bioactivation of the citrus flavonoid

nobiletin by CYP1 enzymes in MCF7 breast

adenocarcinoma cells. Food. Chem. Toxicol. 50 :

3320-3328, 2012.

Sciullo EM, Vogel CF, Wu D, Murakami A,

Ohigashi H and Matsumura F : Effects of

selected food phytochemicals in reducing the

toxic actions of TCDD and p, pʼ-DDT in U937

macrophages. Arch. Toxicol. 84(12) : 957-966,

2010.

佐野宏江，李任時，陳宏斌，古賀貴之，松下武志，

松尾友樹，武田知起，田中嘉孝，石井祐次：ダイ

オキシン母体曝露による胎児ゴナドトロピン低

下機構：胎児視床下部の葉酸代謝系の亢進とaリポ酸補給による回復．フォーラム 2019：衛生

薬学・環境トキシコロジー，京都．8 月 31 日，

2019．

Lowry OH, Rosebrough NJ, Farr AL and

Randall RJ : Protein measurement with the

Folin phenol reagent. J. Biol. Chem. 193 : 265275, 1951.

Burke MD and Mayer RT : Inherent specificities

of purified cytochromes P-450 and P-448

toward biphenyl hydroxylation and ethoxyresorufin deethylation. Drug. Metab. Dispos. 3 :

245-253, 1975.

Fujii-Kuriyama Y and Mimura J : Molecular

mechanisms of AhR functions in the regulation

of cytochrome P450 genes. Biochem. Biophys.

Res. Commun. 338 : 311-337, 2005.

Xu L, Li AP, Kaminski DL and Ruh MF :

2,3,7,8 Tetrachlorodibenzo-p-dioxin induction

of cytochrome P4501A in cultured rat and

human hepatocytes. Chem. Biol. Interact. 124 :

173-189, 2000.

Kuroki J, Koga N and Yoshimura H : High

affinity of 2,3,4,7,8-pentachlorodibenzofuran

to cytochrome P-450 in the hepatic microsomes

of rats. Chemosphere. 15 : 731-738, 1986.

Staskal DF, Diliberto JJ, Devito MJ and Birn-

ノビレチンによる in vitro P450 阻害効果

48)

49)

50)

51)

52)

53)

54)

55)

56)

baum LS : Inhibition of Human and Rat CYP1A2

by TCDD and Dioxin-like Chemicals. Toxicol.

Sci. 84 : 225-231, 2005.

Yeowell HN, Waxman DJ, Wadhera A and

Goldstein JA : Suppression of the constitutive,

male-specific rat hepatic cytochrome P-450 2c

and its mRNA by 3,4,5,3ʼ,4ʼ,5ʼ-hexachlorobiphenyl and 3-methylcholanthrene. Mol. Pharmacol. 32 : 340-347, 1987.

Bhathena A, Lee C and Riddick DS : Suppression

of Cytochrome P450 2C11 by Aromatic Hydrocarbons : Mechanistic Insights from Studies of

the 5-Flanking Region of the CYP2C11 Gene.

Drug. Metab. Dispos. 30 : 1385-1392, 2002.

Oinonen T and Lindros KO : Zonation of hepatic

cytochrome P-450 expression and regulation.

Biochem. J. 329 : 17-35, 1998.

Banerjee S, Das RK and Shapiro BH : Feminization imprinted by developmental growth hormone. Mol. Cell. Endocrinol. 479 : 27-38, 2019.

Kato R and Yamazoe Y : Sex-specific

cytochrome P450 as a cause of sex-and species-related differences in drug toxicity. Toxicol. Lett. 64-65 : 661-667, 1992.

Crofts FG, Sutter TR and Strickland PT :

Metabolism of 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine by human cytochrome

P4501A1, P4501A2 and P4501B1. Carcinogenesis. 19 : 1969-1973, 1998.

Androutsopoulos VP, Tsatsakis AM and Spandidos DA : Cytochrome P450 CYP1A1 : wider

roles in cancer progression and prevention.

BMC. Cancer. 9 : 187, 2009.

El-Sherbeni AA and El-Kadi AO : Characterization of Arachidonic Acid Metabolism by Rat

Cytochrome P450 Enzymes : The Involvement

of CYP1As. Drug. Metab. Dispos. 42 : 14981507, 2014.

Manega CM, Fiorelli S, Porro B, Turnu L,

Cavalca V, Bonomi A, Cosentino N, Di Minno A,

Marenzi G, Tremoli E and Eligini S : 12 (S)

-Hydroxyeicosatetraenoic acid downregulates

monocyte-derived macrophage efferocytosis :

（ 89 ）

57)

58)

59)

60)

61)

62)

147

New insights in atherosclerosis. Pharmacol. Res.

144 : 336-342, 2019.

Zhang XJ, Cheng X, Yan ZZ, Fang J, Wang X,

Wang W, Liu ZY, Shen LJ, Zhang P, Wang PX,

Liao R, Ji YX, Wang JY, Tian S, Zhu XY, Zhang

Y, Tian RF, Wang L, Ma XL, Huang Z, She ZG

and Li H : An ALOX12-12-HETE-GPR31

signaling axis is a key mediator of hepatic

ischemia-reperfusion injury. Nat. Med. 24 : 7383, 2018.

Liu Q, Tan W, Che J, Yuan D, Zhang L, Sun Y,

Yue X, Xiao L and Jin Y : 12-HETE facilitates

cell survival by activating the integrin-linked

kinase/NF-kB pathway in ovarian cancer.

Cancer. Manag. Res. 10 : 5825-5838, 2018.

Honn KV, Tang DG, Gao X, Butovich IA, Liu B,

Timar J and Hagmann W : 12-lipoxygenases

and 12 (S) -HETE : role in cancer metastasis.

Cancer. Metastasis. Rev. 13 : 365-396, 1994.

Diani-Moore S, Ma Y, Gross SS and Rifkind AB :

Increases in levels of epoxyeicosatrienoic and

dihydroxyeicosatrienoic acids (EETs and

DHETs) in liver and heart in vivo by

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)

and in hepatic EET : DHET ratios by cotreatment with TCDD and the soluble epoxide

hydrolase inhibitor AUDA. Drug. Metab. Dispos. 42 : 294-300, 2014.

Wiest EF, Walsh-Wilcox MT, Rothe M, Schunck

WH and Walker MK : Dietary Omega-3 Polyunsaturated Fatty Acids Prevent Vascular Dysfunction and Attenuate Cytochrome P4501A1

Expression by 2,3,7,8- TetrachlorodibenzoP-Dioxin. Toxicol. Sci. 154 : 43-54, 2016.

Labitzke EM, Diani-Moore S and Rifkind AB :

Mitochondrial P450-dependent arachidonic acid

metabolism by TCDD-induced hepatic

CYP1A5; conversion of EETs to DHETs by

mitochondrial soluble epoxide hydrolase. Arch.

Biochem. Biophys. 468 : 70-81, 2007.

(Received for publication March 9, 2021)

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