Genoprotection and genotoxicity of green tea (Camellia sinensis): Are they two sides of the same redox coin?

Figures & data

Table 1. Estimated catechins concentrations (μmol/l) of the tea solutions used in the in vitro study

	Catechins concentration of green tea at
Catechin	0.005% w/v	0.01% w/v	0.05% w/v
Epigallocatechin gallate	3.6	7.1	35.7
Epigallocatechin	1.9	3.8	19.0
Epicatechin gallate	0.77	1.5	7.7
Epicatechin	0.73	1.4	7.3
Catechin	0.1	0.3	1.3
Total catechins	7.1	14.2	71

Table 2. Concentrations of H₂O₂ measured in freshly prepared tea infusions (in PBS) and after 30 minutes at 37°C; data are mean (SD), n = 3

	Concentration of H2O2 (mol/l) in
	0.005% Green tea	0.01% Green tea	0.05% Green tea
Freshly prepared solutions of tea	1.41 (0.10)	1.57 (0.07)	3.61 (0.58)
The same tea solutions after 30 minutes at 37°C	3.52 (1.18)	7.36 (1.64)*	51.73 (3.98)*

*P < 0.05 Compared to the fresh tea solution of the same concentration.

Table 3. DNA damage in cells treated with green tea or green tea + catalase for 30 minutes at 37°C

	Green tea (% w/v in PBS)				Green tea (% w/v in PBS) + catalase
	0% (PBS)	0.005% Tea	0.01% Tea	0.05% Tea	0% (PBS)	0.005% Tea	0.01% Tea	0.05% Tea
%DNA in tail	12.99 (1.14)	8.52* (0.25)	9.57* (0.21)	19.72*^,# (1.41)	13.24 (0.41)	9.25* (0.99)	9.02* (0.99)	11.24 (1.28)

Data are mean (SD) %DNA in tail, n = 3 (Fpg-assisted comet assay used).

*P < 0.001 Compared to PBS-treated (no tea) cells in same set; ^#P < 0.001 compared to lower concentrations of green tea in same set.