Table 5.

Effect of Ag-NPs on mRNA expression (relative expression to β-actin) of antioxidant genes in brain of O. niloticus and T. zillii.

Fish	Group	CAT	SOD	GST	GR	GP
O. niloticus	Control	23.4 ± 3	7.4 ± 0.6	172 ± 11	1.4 ± 0.19	42 ± 8
	2 mg/L	20 ± 2.7	10 ± 2	160 ± 15	1.2 ± 0.1	39 ± 8
	4 mg/L	14 ± 2∗∗,#	2 ± 0.2∗∗,##	100 ± 9∗∗∗,###	0.8 ± 0.1∗∗,#	20 ± 3∗∗∗,###
T. zillii	Control	30 ± 2.5	7.8 ± 1	166 ± 8	1.66 ± 0.17	37.8 ± 10
	2 mg/L	28 ± 2.5	11 ± 1.3	150 ± 13	1.4 ± 0.23	34 ± 6
	4 mg/L	11 ± 3∗∗,##	2.2 ± 1∗∗,##	110 ± 8∗∗∗,##	0.7 ± 0.12∗∗∗,##	25 ± 6∗∗∗,##

^**P < 0.01, ^***P < 0.001, compared to control group of the same fish species; ^#P < 0.05, ^##P < 0.01, ^###P < 0.001, comparing to 2 mg/L Ag-NPs exposed group of the same fish species.