MOURA Dinara Jaqueline et al.

Table II. Induction of forward mutation (can1) in haploid N123 strain of
Saccharomyces cerevisiae after b-carbolinic alkaloids treatments in stationary
phase in PBS
Agent Treatment (lg/ml) Survival (%) Can/10 7 survivors a
NC b
0 100 (237) c
1.05 0.57 d
4NQO e
0.5 45.14 (107)*** 30.28 3.43***
Harmane 10 98.78 (234) 2.54 0.02
25 91.71 (217) 1.98 1.03
50 87.23 (207) 2.55 0.42
Harmine 10 96.55 (228) 1.71 0.45
25 93.13 (221) 1.39 0.52
50 90.72 (215) 2.77 0.36
Harmol 10 90.71 (215) 1.90 0.59
25 88.30 (209) 2.08 0.42
50 86.56 (205) 2.23 0.43
Harmaline 10 96.63 (229) 1.55 0.29
25 95.47 (226) 1.65 0.98
50 93.96 (222) 2.03 0.30
Harmalol 10 92.26 (219) 1.25 0.75
25 91.49 (217) 1.97 0.28
50 89.23 (211) 2.03 0.24
a
Locus-specific revertants.
b
Negative control (solvent).
c
Number of colonies.
d
Mean and standard deviation per three independent experiments.
e
Positive control.
Data significant in relation to negative control group (solvent) at
***P , 0.001/one-way ANOVA–Tukey’s multiple comparison test.
Table III. Effects of b-carbolinic alkaloids on induced mutagenicity by H 2O 2
in haploid N123 strain of Saccharomyces cerevisiae in the stationary phase
in PBS
Agent Treatment Survival (%) Can/10 7 survivors a
NC b
0 100 (247) c
1.02 0.12 d
e
H2O2 4 mM 42.10 (104) 19.29 2.08
Harmane
Harmine
Harmol
Harmaline
Harmalol
10 lg/ml þ H2O2
25 lg/ml þ H2O2
50 lg/ml þ H2O2
10 lg/ml þ H2O2
25 lg/ml þ H2O2 50 lg/ml þ H2O2 10 lg/ml þ H2O2 25 lg/ml þ H2O2
50 lg/ml þ H2O2
10 lg/ml þ H2O2
25 lg/ml þ H2O2
50 lg/ml þ H2O2 10 lg/ml þ H2O2 25 lg/ml þ H2O2
50 lg/ml þ H2O2
74.89 (185)
69.73 (172)
67.20 (166)
70.85 (175)
60.42 (149)
55.46 (137)
79.77 (197)
72.82 (180)
61.34 (152)
65.47 (162)
67.26 (166)
73.99 (183)
68.70 (170)
74.89 (185)
71.25 (176)
5.67
6.99
9.64
5.95
7.49
13.5
4.46
4.93
10.92
4.44
6.68
7.59
8.88
4.38
1.98
0.80***
0.10**
1.81**
0.38***
1.11**
1.57*
0.57***
0.41***
2.26*
0.22***
1.66**
3.15**
1.30**
0.32***
0.19***
a Locus-specific revertants.
b Negative control (solvent).
c Number of colonies.
d Mean and standard deviation per three independent experiments.
e Positive control (H2O 2).
Data significant in relation to positive control group at *P , 0.05, **P , 0.01
and ***P , 0.001/one-way–ANOVA Tukey’s multiple comparison test.
oxidative stress induced by H2O2, and it has been shown that
there is a strong relationship between catalase and SOD activities
under different experimental conditions. Therefore, the lack of
SOD as well as of catalase activities imputes sensitivity to H2O2.
Thus, we believe that the protective effect against paraquat
toxicity can be due to the direct action against H2O2 or against
OH_ radical generated through the Haber-Weiss–Fenton re-
Table IV. Effects of b-carbolines alkaloids in V79 cells exposed for 2 h and
evaluated by comet assay
Substance Treatment DI a
NC b
MMS c
DF (%) a
0 46.00 4.00 49.00 2.00
4.0 10 5 M 227.00 4.35*** 86.00 9.84***
Harmane 10 lg/ml 80.00 8.93 41.33 3.05
20 lg/ml 84.33 3.79 58.00 3.00
40 lg/ml 182.71 6.19** 69.66 1.57*
Harmine 10 lg/ml 74.00 16.28 54.33 4.61
20 lg/ml 81.01 0.73 65.66 6.42
40 lg/ml 113.2 4.58* 71.64 1.82*
Harmol 10 lg/ml 82.68 5.85 54.33 3.53
20 lg/ml 80.02 13.89 56.00 2.00
40 lg/ml 103.33 7.57* 58.30 14.97
80 lg/ml 150.00 12.76*** 72.00 5.29**
Harmaline 10 lg/ml 49.66 20.42 35.66 10.96
20 lg/ml 66.34 11.93 50.60 7.8
40 lg/ml 80.67 10.42 52.62 4.72
80 lg/ml 79.00 13.51 54.00 7.20
Harmalol 10 lg/ml 55.38 6.65 48.66 10.96
20 lg/ml 58.66 4.60 50.00 4.35
40 lg/ml 63.05 2.83 52.66 10.59
80 lg/ml 62.33 15.53 53.65 8.62
a
Means values and standard deviation obtained from average of 100 cells per
experiment—total of four experiments per dose for each substance.
b
Negative control (solvent).
c
Positive control.
Data significant in relation to negative control (solvent) groups at *P , 0.05,
**P , 0.01 and ***P , 0.001/one-way ANOVA–Tukey’s multiple
comparison test.
Table V. Effect of b-carboline alkaloids in V79 cells exposed for 2 h plus
oxidant H2O2 for 0.5 h and evaluated by comet assay
Substance Treatment DI a
NC b
Antioxidant properties of b-carboline alkaloids
DF (%) a
0 46.35 4.83 22.45 6.11
c
H2O2 100 lM 219.66 36.08 86.36 6.35
Harmane
Harmine
Harmol
Harmaline
Harmalol
10 lg/ml þ H2O2 20 lg/ml þ H2O2
10 lg/ml þ H2O2
20 lg/ml þ H2O2
10 lg/ml þ H2O2
20 lg/ml þ H2O2 10 lg/ml þ H2O2 20 lg/ml þ H2O2 40 lg/ml þ H2O2
10 lg/ml þ H2O2
20 lg/ml þ H2O2
40 lg/ml þ H2O2
92.33
122.00
106.00
123.33
92.66
108.66
106.33
107.66
106.00
86.33
112.33
115.33
13.79***
6.00***
21.96***
24.58*
11.60***
19.03***
11.93***
7.57***
1.73***
12.85***
8.38***
17.00***
41.33
58.00
55.66
67.33
44.33
56.33
60.00
50.33
54.33
50.00
49.66
54.66
3.05***
3.00**
6.42**
2.30
2.51***
2.00**
7.80***
15.71***
4.61***
11.36***
4.93***
3.51***
a
Mean values and standard deviation obtained from average of 100 cells per
experiment—total of four experiments for each substance.
b
Negative control (solvent).
c
Positive control (H2O2).
Data significant in relation to positive control (oxidant) group at *P , 0.05,
**P , 0.01 and ***P , 0.001/one-way ANOVA–Tukey’s multiple
comparison test.
action, since there are evidences demonstrating that these
alkaloids are not active against superoxide anions in vitro when
tested using SOD-inhibitable reduction ferricytochrome c (36).
It is also important to note the antioxidant response observed
in the yap1 mutants for most alkaloid treatments, especially for
the dihydro-b-carbolines (Figures 3D, 3E, 4D and 4E). Yap1
is a key regulator of oxidative stress tolerance in S. cerevisiae,
and has been shown to regulate a broad set of genes in response
to oxidative stress, including TRX2 (thioredoxin), TRR1
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