Dimethyl itaconate

Basic toxicokinetics

Administrative data

Endpoint:

basic toxicokinetics

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: meets basic scientific principles non-GLP

Data source

Reference

Reference Type:

publication

Title:

Identification of a common chemical signal regulating the induction of enzymes that protect against chemical carcinogenesis.

Author:

Talalay P, De Long MJ, Prochaska HJ.

Year:

1988

Bibliographic source:

Proc Natl Acad Sci U S A. 1988 Nov;85(21):8261-5. PMID: 3141925

Materials and methods

Objective of study:

metabolism

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Several chemicals featuring a Michael-System were tested including dimethyl itaconate (DMI) and results summarized in a survey article.
- in vitro experiment: Hepa 1c1c7 murine hepatoma cells treated with various concentrations of the test item in a cell culture system and the concentration needed for doubling of quinone reductase activity (QR) was determined
- in vivo experiment: Female CD1 mice were treated with 25 or 75 µmol of the test items via gavage for 5 days. After sacrifice QR and glutathione-S-transferase (GST) activities were determined in liver, forestomach and glandular stomach.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Dimethyl itaconate

EC Number:

210-519-6

EC Name:

Dimethyl itaconate

Cas Number:

617-52-7

Molecular formula:

C7H10O4

IUPAC Name:

1,4-dimethyl 2-methylidenebutanedioate

Details on test material:

- Name of test material (as cited in study report): dimethyl itaconate
- Physical state: not reported
- Analytical purity: All compounds were of the highest quality obtainable commercially and were purified when necessary.
- No further details reported in this survey article.

Radiolabelling:

no

Test animals

Species:

mouse

Strain:

CD-1

Sex:

female

Details on test animals or test system and environmental conditions:

- in vitro experiment: not applicable
- in vivo experiment:

TEST ANIMALS
- Age at study initiation: 6 wks
- Weight at study initiation:
- Fasting period before study:
- Housing:
- Individual metabolism cages: yes/no
- Diet (e.g. ad libitum):
- Water (e.g. ad libitum):
- Acclimation period:

ENVIRONMENTAL CONDITIONS
- Temperature (°C):
- Humidity (%):
- Air changes (per hr):
- Photoperiod (hrs dark / hrs light):

IN-LIFE DATES: From: To:

Administration / exposure

Route of administration:

other: oral (gavage) in the in vivo experiment

Vehicle:

other: in the in vivo experiment: Emulphor EL620P

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
in indicated single daily doses in 0.1 mL of Emulphor EL620P

VEHICLE
- Justification for use and choice of vehicle (if other than water): not given, but Emulphor is an often used vehicle in toxicologic experiments
- Concentration in vehicle: 250 and 750 mMol/L
- Amount of vehicle (if gavage): 0.1 mL
- Purity: not reported

Duration and frequency of treatment / exposure:

- in vitro experiment: not applicable
- in vivo experiment: once daily (for 5 days)

Doses / concentrations

Remarks:

Doses / Concentrations:
- in vitro: concentration above and below 35 µM (details not reported)
- - in vivo experiment: 25 and 75 µMol

No. of animals per sex per dose / concentration:

- in vitro experiment: not applicable
- in vivo experiment: 3 - 6 per group

Control animals:

other: in vivo experiment: yes, concurrent vehicle

Positive control reference chemical:

- in vitro experiment: no
- in vivo experiment: BHA, 2(3)-tert-butyl-4-hydroxyanisole

Details on study design:

- Dose selection rationale: not reported
- Rationale for animal assignment (if not random): not reported

Details on dosing and sampling:

not applicable

Statistics:

no statistics used beyond determination of averages and standard deviations

Results and discussion

Preliminary studies:

not applicable

Toxicokinetic / pharmacokinetic studies

Details on absorption:

not applicable

Details on distribution in tissues:

not applicable

Details on excretion:

not applicable

Metabolite characterisation studies

Metabolites identified:

no

Details on metabolites:

not applicable

Any other information on results incl. tables

- Table 1: Concentration (CD) of fumarate, maleate, and itaconate derivatives required to double quinone reductase in Hepa Lc1c7 cells

		Compound	CD, µM
No.	Name	Structure
33	Fumaric acid	HOOCCH=CHCOOH (trans)	I
34	Dimethyl fumarate	CH3OOCCH=CHCOOCH3 (trans)	22
35	Diethyl fumarate	C2H5OOCH=CHCOOC2H5 (trans)	100
36	Maleic acid	HOOCCH=CHCOOH (cis)	I
37	Dimethyl maleate	CH3OOCCH=CHCOOCH3 (cis)	20
38	Diethyl maleate	C2H5OOCCH=CHCOOC2H5 (cis)	40
39	Dimethyl succinate	CH3OOCCH2CH 2C 00CH3	I
40	Dimethyl itaconate	CH3OOCC(=CH2)CH2COOCH3	35

I: inactive; <20% increase in specific activity at 200 µM.

CD: concentration at which QR activity was doubled

Dimethyl itaconate was a moderately potent inducer with a CD value of 35 µM.

- Table 2: Induction patterns of QR and GSTs (the latter measured with CDNB and DCNB) in mouse tissues.

Inducing agent	Dose, µmol per mouse per day	Enzyme	Ratio of specific activities (treated/control)
			Liver	Forestomach	Glandular stomach
Dimethyl itaconate	25	QR	2.37 ± 0.22	2.74 ± 0.11	2.63 ± 0.13
	25	GST (CDNB)	1.79 ± 0.06	3.47 ± 0.06	5.07 ± 0.53
	25	GST (DCNB)	0.90 ± 0.06	4.34 ± 0.30	6.73 ± 0.71
	75	QR	3.30 ± 0.05	2.73 ± 0.15	2.90 ± 0.07
	75	GST (CDNB)	2.79 ± 0.07	4.27 ± 0.28	6.71 ± 0.30
	75	GST (DCNB)	1.71 ± 0.08	4.90 ± 0.22	7.75 ± 0.57
Absolute values of vehicle controls (nmol/min/mg of protein ± SEM)
Vehicle control	0	QR	126 ± 3.3	1454 ± 88	3955 ± 187
	0	GST (CDNB)	1800 ± 30	1130 ± 69	684 ± 40
	0	GST (DCNB)	37.9 ± 3.9	15.6 ± 0.8	8.35 ± 1.06

The SEM values of the treated/control ratios were obtained by dividing the SEM of the mean of each treated group by the control value. CDNB: 1-chloro-2,4-dinitrobenzene; DCNB: 1,2 -dichloro-4-nitrobenzene Citation from the article: "The results in mice in vivo are similar to the findings obtained with Hepa lcic7 cells. With few exceptions, all compounds induced all three enzyme activities and, for the most part, coordinately. Furthermore, several of the new electrophiles were more potent and more effective than BHA and tert-butylhydroquinone. For example, in the glandular stomach, phase II enzymes are only slightly responsive to BHA and tert-butylhydroquinone (9, 10), whereas five doses of 25 µmol of dimethyl itaconate raised the enzyme specific activities 2.63- to 6.73-fold. Examination of the least toxic of these compounds with widest tissue specificity will, therefore, be of great interest in cancer protection experiments in vivo. Chemoprotection by these new compounds would further strengthen the view that enzyme induction is a central mechanism of chemoprotection."

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): other: Dimethyl itaconate is a relatively potent inducer of phase II metabolic enzymes
Dimethyl itaconate (DMI) was tested in vitro (in Hepa 1c1c7 murine hepatoma cells) for its potency to induce quinone reductase activity as surrogate for phase II metabolic enzymes. In addition in an in vivo experiment in female CD1 mice treated 5 d via gavage with DMI the induction of QR and glutathione-S-transferase (GST) activity was measured. Both experiments led to the conclusion that DMI is a relatively potent inducer of phase II metabolic enzymes.

Executive summary:

Dimethyl itaconate (DMI) was tested in vitro (in Hepa 1c1c7 murine hepatoma cells) for its potency to induce quinone reductase (QR) activity as surrogate for phase II metabolic enzymes. In addition in an in vivo experiment in female CD1 mice treated 5 d via gavage with DMI the induction of QR and glutathione-S-transferase (GST) activity was measured.

In the in vitro experiment Hepa lc1c7 murine hepatoma cells were grown in microtiter plates and the QR activity measured after incubation with the test item.

In the in vivo experiment the compound was administered in single daily doses in 0.1 ml of Emulphor EL620P for 5 days. Cytosols were prepared from the tissues 24 hr after the last treatment and assayed for enzyme activities (using CDNB (1 -chloro-2,4 -dinitrobenzene) and DCNB (1,2 -dichloro-4 -nitrobenzene) as substrates for GST).

Both experiments led to the conclusion that DMI is a relatively potent inducer of phase II metabolic enzymes.

Dimethyl itaconate was a moderately potent inducer compared to other "Michael acceptor" substances with a CD value (concentration at which the QR activity was doubled) of 35 µM in the invitro experiment.

In the in vivo experiment dimethyl itaconate was more potent and more effective than BHA (2(3)-tert-butyl-4-hydroxyanisole) and tert-butylhydroquinone, know inducers of phase II metabolism. In the glandular stomachof female mice, phase II enzymes are only slightly responsive to BHA and tert-butylhydroquinone, whereas five doses of 25 µmol of dimethyl itaconate raised the enzyme specific activities 2.63- to 6.73-fold.