Registration Dossier

Administrative data

Endpoint:
additional toxicological information
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
No data
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Meets generally accepted scientific standards with acceptable restrictions.

Data source

Reference
Reference Type:
publication
Title:
Antimutagenesis studies of magnesium and calcium salts
Author:
Bronzetti G, Aretini P et al
Year:
2000
Bibliographic source:
Journal of Environmental Pathology, Toxicology and Oncology 19 (4): 401 - 413.

Materials and methods

Type of study / information:
Antimutagenesis study of calcium salts.
Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Calcium salts of the typecorresponding to magnesium and their protective role agains oxidative damage of free radicals and enzymatic activities, such as catalase, glutathione peroxidase and superoxide dismutase, which are involved in antioxidative defenses.
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Test substance: magnesium salts (sulfate) and calcium salts (CaCl2, CaSO4 and CaCO3).

Results and discussion

Any other information on results incl. tables

Magnesium salts (MgSO4) in various concentrations differently affected the yeast cells after treatment with H2O2. Survival of the yeast cells was reduced after treatment with H2O2 and the toxicity was more marked in the logarithmic phase cells than in the stationary-phase cells. After treatment with H2O2 the survival from the stationary phase was about 80 %.

Magnesium sulfate decreased the mitotic gene conversion rate induced by H2O2 at a concentration of about 400 mM in cells from stationary phase a two concentrations used, whereas in cells from logarithmic phase, it exerted antimutagenic effects, both from mitotic gene conversion and point-reverse mutation.

Calcium salts (CaCl2, CaSO4 and CaCO3) used in the stationary phase did not show any mutagenic and anitmutagenic effects after induction with H2O2 (200 and 400 mM). Calcium chloride exerted major toxic effects compared with the other salts used. Calcium carbonate at a concentration of 100 mM reduced the growth of yeast cells by 5 % and calcium sulfate had about the same effect. Toixicityof calcium salts was more marked in the logarithmic phase cells than in the stationary phase cells. Therefore no antimutagenic effects could be demonstrated.

Catalase was not activated by magnesium sulfate. Experiments with calcium salts did not show any mutagenic or antimutagenic effects or variation in the level of enzyme activity examined.

Effects of calcium salts on gene conversion (GC) and point mutation (PM) frequencies induced by hydrogen peroxide (H2O2) in stationary phase(SP) cells of D7 strain of the yeast S. cerevisiae:

Group

Experiment

Calcium salts (SP)

Surv. (%)

GC/105surv.

PM/106surv.

I

Control

100

1.08 ± 0.39

0.81 ± 0.26

II

H2O2200 mM

82.00 ± 18.70

8.45 ± 1.10*

7.34 ± 2.30*

III

H2O2400 mM

86.50 ± 17.40

13.42 ± 2.81*

9.90 ± 1.40*

IV

CaCl2100 mM

73.00 ± 25.93

1.15 ± 0.42

1.39 ± 0.26

V

CaCl210 mM+ H2O2200 mM

74.67 ± 22.17

8.57 ± 1.72

9.06 ± 1.64

VI

CaCl2100 mM+ H2O2200 mM

67.00 ± 25.47

9.73 ± 0.62

11.18 ± 4.2

VII

CaCl210 mM+ H2O2400 mM

74.30 ± 24.10

15.66 ± 2.72

11.80 ± 2.25

VIII

CaCl2100 mM+ H2O2400 mM

68.70 ± 28.50

15.97 ± 2.45

10.83 ± 0.09

IX

CaSO4100 mM

89.00 ± 15.50

1.19 ± 0.11

0.52 ± 0.12

X

CaSO410 mM+ H2O2200 mM

71.30 ± 22.50

6.67 ± 2.50

6.89 ± 0.68

XI

CaSO4100 mM+ H2O2200 mM

66.30 ± 25.30

11.83 ± 0.06

11.45 ± 1.41

XII

CaSO410 mM+ H2O2400 mM

76.60 ± 22.40

11.90 ± 2.75

12.35 ± 3.23

XIII

CaSO4100 mM+ H2O2400 mM

67.70 ± 27.90

14.56 ± 3.33

13.45 ± 2.71

XIV

CaCO3100 mM

95.00 ± 5.00

1.20 ± 0.06

0.78 ± 0.21

XV

CaCO325 mM+ H2O2200 mM

86.30 ± 19.30

8.45 ± 0.28

6.06 ± 2.25

XVI

CaCO350 mM+ H2O2200 mM

92.70 ± 10.40

9.03 ± 0.31

6.46 ± 1.35

XVII

CaCO3100 mM+ H2O2200 mM

94.30 ± 8.00

9.44 ± 0.34

6.37 ± 2.37

XVIII

CaCO325 mM+ H2O2400 mM

84.30 ± 12.00

16.60 ± 1.88

10.59 ± 2.07

XIX

CaCO350 mM+ H2O2400 mM

84.00 ± 22.60

15.46 ± 2.51

12.07 ± 3.80

XX

CaCO3100 mM+ H2O2400 mM

88.30 ± 16.50

20.17 ± 5.74

9.38 ± 2.35

Data are reported as means of three independent experiments ± standard deviation (* p ≤ 0.05). For statistical analysis the following independent data are compared: II, III, IV, XI, XIV with I, V,VI, X, XI, XV, XVI, XVII with II, VII, VIII, XII, XIII, XVIII, XIX, XX with III.

Effects of calcium salts on gene conversion (GC) and point mutation (PM) frequencies induced by hydrogen peroxide (H2O2) in logarithmic phase (LP) cells of the D7 strain of the yeast S. cerevisiae.

Group

Experiment

Calcium salts (LP)

Surv. (%)

GC/105surv.

PM/106surv.

I

Control

100

2.41 ± 0.25

1.12 ± 0.22

II

H2O250 mM

76.75±5.72

10.13 ± 2.36*

14.29 ± 1.67*

III

H2O2100 mM

43.50 ± 8.96

53.01 ± 9.8*

23.56 ± 1.99*

IV

CaCl2100 mM

55.33 ± 10.78

2.22 ± 0.11

1.2 ± 0.38

V

CaCl210 mM+ H2O250 mM

51.50 ± 13.01

48.30 ± 13.56

20.21 ± 5.44

VI

CaCl2100 mM+ H2O250 mM

71.67 ± 5.56

45.09 ± 5.71

15.14 ± 3.81

VII

CaCl210 mM+ H2O2100 mM

56.00 ± 5.00

49.17 ± 14.41

22.25 ± 5.17

VIII

CaCl2100 mM+ H2O2100 mM

43.67 ± 16.66

86.02 ± 19.74

16.59 ± 4.50

IX

CaSO4100 mM

79.00 ± 9.00

2.59 ± 0.23

2.29 ± 1.86

X

CaSO410 mM+ H2O250 mM

82.67 ± 1.70

44.95 ± 14.83

10.58 ± 2.37

XI

CaSO4100 mM+ H2O250 mM

8.00 ± 5.00

41.34 ± 6.31

11.70 ± 1.97

XII

CaSO410 mM+ H2O2100 mM

46.87 ± 5.22

63.02 ± 23.40

27.23 ± 3.30

XIII

CaSO4100 mM+ H2O2100 mM

88.50 ± 11.50

43.89 ± 12.72

18.03 ± 5.64

XIV

CaCO3100 mM

90.67 ± 10.07

1.49 ± 0.53

0.82 ± 0.15

XV

CaCO325 mM+ H2O250 mM

71.00 ± 21.63

35.00 ± 3.90

13.76 ± 0.46

XVI

CaCO350 mM+ H2O250 mM

89.00 ± 14.93

36.34 ± 4.25

12.01 ± 0.27

XVII

CaCO3100 mM+ H2O250 mM

87.30 ± 11.59

39.46 ± 9.81

11.24 ± 2.97

XVIII

CaCO325 mM+ H2O2100 mM

40.00 ± 18.00

37.48 ± 6.40

22.21 ± 0.23

XIX

CaCO350 mM+ H2O2100 mM

50.67 ± 21.59

35.83 ± 5.56

21.37 ± 3.54

XX

CaCO3100 mM+ H2O2100 mM

41.33 ± 4.72

56.02 ± 13.74

22.73 ± 0.50

Dat are reported as means of three independent experiments ± standard deviation (*p ≤ 0.05). For statistical analysis the following independent data are compared: II, III, IV, IX, XIV with I, V, VI, X, XI, XV, XVI, XVII with II, VII, VIII, XII, XIII, XVIII, XIX, XX with III.

Effects of magnesium salts on yeast antioxidant enzymatic activities:

Test

Concentration

Catalase

(20 %)

GSH-Peroxidase

(0.5 %)

Superoxide

dismutase

(20 %)

Cytochrome P-450

0.5 %

20 %

Control

-

5.92 ± 2.21

19.00 ± 3.74

33.80 ± 3.50

1.73 ± 0.45

9.30 ± 0.26

MgSO4

0.25 mM

8.61 ± 0.88

46.50 ± 2.50*

132.26 ± 9.82*

2.43 ± 0.62

9.25 ± 0.78

2.5 mM

9.18 ± 1.13

49.67 ± 1.70*

252.03 ± 7.46*

1.91 ± 0.32

9.58 ± 0.63

25 mM

8.81 ± 1.60

51.33 ± 8.73*

132.61 ± 9.11*

2.02 ± 0.19

9.52 ± 0.12

50 mM

8.78 ± 0.61

54.50 ± 4.50*

276.36 ± 13.7*

2.16 ± 0.26

9.31 ± 0.63

100 mM

9.97 ± 1.35

62.00 ± 1.30*

364.28 ± 10.9*

1.61 ± 0.15

9.73 ± 0.81

Data are reported as means of three independent experiments ± standard deviation (*p < 0.05). μmoles of H2O2/min.mg.prot; nmoles of oxided NAPDH/min.mg/prot; pmles of cytochrome P-450/mg.prot.

Effect of calcium salt of yeast antioxidant enzymaric activities:

Test

Concentration

Catalase

(20 %)

GSH-Peroxidase

(0.5 %)

Superoxide

dismutase

(20 %)

Control

-

5.92 ± 2.21

19.00 ± 3.74

33.80 ±3.50

CaSO4

0.25 mM

5.76 ± 0.70

18.75 ± 1.91

36.29 ± 0.90

2.5 mM

6.20 ± 0.50

18.75 ± 2.61

30.46 ± 0.90

25 mM

6.10 ± 0.94

26.32 ± 3.02

n.d.

50 mM

6.14 ± 1.45

n.d.

n.d.

100 mM

5.07 ± 0.63

n.d.

n.d.

Data are reported as means of three independent experiments ± standard deviation. μmoles of H2O2/min.mg.prot; nmoles of oxidized NADPH/min.mg.prot; SOD units/mg.prot.

Applicant's summary and conclusion

Conclusions:
Calcium salts did not induce any antimutagenic activity.