Triphenyl phosphite

Specific investigations: other studies

Administrative data

Endpoint:

endocrine system modulation

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

28.11.2012 - 05.12.2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: recent study conducted according to reliable in-house protocol

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

Method performed according to P. Sohoni and J.P. Sumpter (1998)

The aim of the study was to determine the androgenic and antiandrogenic potential of the test item. The yeast cells used in the yeast androgen screening (YAS) assay have been stably transformed with genes for the human androgen receptor and the ß-galactosidase reporter gene. Androgenic as well as antiandrogenic potentials of the test substances mediated by receptor binding or blocking can be determined using this assay, respectively.

GLP compliance:

no

Type of method:

in vitro

Test material

Test material information

Constituent 1

Reference substance name:

Triphenyl phosphite

EC Number:

202-908-4

EC Name:

Triphenyl phosphite

Cas Number:

101-02-0

Molecular formula:

C18H15O3P

IUPAC Name:

triphenyl phosphite

Details on test material:

- Name of test material: Triphenyl phosphite
- Physical state: Liquid, yellowish
- Storage condition of test material: Room temperature

Test animals

Species:

other: Yeast

Details on test animals or test system and environmental conditions:

The yeast strain was cultivated by orbital shaking (85 rpm) at approximately 32°C for 24 - 72 h. For this 100 ml culture medium was inoculated with a thawed aliquot of yeast stock culture. Optical density (OD) was measured at 690 nm and the test culture prepared. As a rule, 0.5 ml of the preculture with an OD of 1.0 was transferred into 50 ml fresh growth medium including 0.5 ml chromogenic substrate CPRG (chlorophenolred-ß-D-galactopyranoside).

Administration / exposure

Route of administration:

other: in vitro application

Vehicle:

DMSO

Duration of treatment / exposure:

48h

Frequency of treatment:

Once

Doses / concentrations

Remarks:

10E-10, 10E-9, 10E-8, 10E-7, 10E-6, 10E-5, 10E-4 mol/L

Control animals:

yes

Details on study design:

The study was carried out in 96-well microtiter plates in which 2 µL of different test substance concentrations were pipetted. Afterwards 200 µL of the test culture containing the chromogenic substrate CPRG were added to each well, the plates were sealed with adhesive tape and incubated on an orbital shaker at about 32°C until measurement of the OD. After 48 h (+/- 4 h) incubation, absorbance of the plates was measured at 570 nm (color development, androgen receptor dependent enzyme expression) and 690 nm (turbidity due to growth of the yeast).

Examinations

Examinations:

Evaluation was performed by calculating the difference of the measured ODs at the two wavelengths (absorption at 570 nm - absorption at 690 nm).

Positive control:

Yes
- Androgenic positive control: Dihydrotestosterone (10E -11, 10E-10, 10E-9, 5*10E-9, 10E-8, 10E-7, 10E-6 mol/L)
- Antiandrogenic positive control: Dihydrotestosterone (5*10E-9 mol/L combined with hydroxyflutamide 10E-5 mol/L)

Results and discussion

Details on results:

ln this study, the test substance did not show androgenic activity in comparison to dihydrotestosterone. ln this study, the test substance showed clear antiandrogenic activity at 10E-05 mol/L in comparison to hydroxyflutamide. No cytotoxicity was observed.

Applicant's summary and conclusion

Conclusions:

Based on the results of this study, the test substance showed no androgenic activity in comparison to dihydrotestosterone. ln this study, the test substance showed clear antiandrogenic activity at 10E-05 mol/L in comparison to hydroxyflutamide. No cytotoxicity was observed.

Executive summary:

The yeast strain was cultivated by orbital shaking (85 rpm) at approximately 32°C for 24 - 72 h. For this 100 ml culture medium was inoculated with a thawed aliquot of yeast stock culture. Optical density (OD) was measured at 690 nm and the test culture prepared. As a rule, 0.5 ml of the preculture with an OD of 1.0 was transferred into 50 ml fresh growth medium including 0.5 ml chromogenic substrate CPRG (chlorophenolred-ß-D-galactopyranoside). The study was carried out in 96-well microtiter plates in which 2 µL of different test substance concentrations were pipetted. Afterwards 200 µL of the test culture containing the chromogenic substrate CPRG were added to each well, the plates were sealed with adhesive tape and incubated on an orbital shaker at about 32°C until measurement of the OD. After 48 h (+/- 4 h) incubation, absorbance of the plates was measured at 570 nm (color development, androgen receptor dependent enzyme expression) and 690 nm (turbidity due to growth of the yeast). Evaluation was performed by calculating the difference of the measured ODs at the two wavelengths (absorption at 570 nm - absorption at 690 nm). Each experiment includes negative controls (vehicle controls) and positive controls for the verification of the androgenic (dihydrotestosterone 10 ^-11, 10^-10, 10^-9, 5*10^-9, 10^-8, 10^-7, 10^-6 mol/L) and antiandrogenic (dihydrotestosterone 5*10^-9 mol/L combined with hydroxyflutamide 10^-5 mol/L) activity of the yeast cells.

 

Final concentration of test material [mol/L]: 10^-10, 10^-9, 10^-8, 10^-7, 10^-6, 10^-5, 10^-4