Mitigating potential of Melissa officinale against As3+-induced cytotoxicity and transcriptional alterations of Hsp70 and Hsp27 in fish, Channa punctatus (Bloch).

The mitigating potential of Melissa officinale (MO) (Lamiaceae) against arsenite (As3+)-induced oxidative stress, cytogenotoxicity, and expression of stress genes in fish, Channa punctatus (Bloch), teleost, was explored. After confirming the composition of MO extract, caffeic acid (0.96%), hesperidin (1.73%), naringenin (7.70%), lutenolin (3.29%), kaempferol (11.46%) and hesperetin (6.24%), by HPLC-PDA analysis, the experiment was set up in six groups (G1-G6), each containing 10 specimens. Blood, muscle, gills and liver tissues of control and treated fishes were excised at an interval of 24 till 96 h. Ameliorative potential of MO was confirmed by satisfactory restoration of altered activities of malondialdehyde, hydrogen peroxide, superoxide dismutase, catalase, glutathione peroxidise, glutathione reductase, reduced glutathione and ascorbate peroxidase in G4, G5 and G6, co-exposed with 96 h-LC50/10 As3+ with MO. A significant (p < 0.05) recovery in the frequencies of cytogenotoxic markers, micronuclei, disintegrated nucleus and echinocytes, which were expressed significantly (p < 0.05) in G3 exposed to sub-lethal concentration of ATO alone, was recorded in fish groups (G4, G5 and G6) together treated with 96 h-LC50/10 of ATO and 2, 4 and 8 ppm of MO, respectively. Moreover, the expression of Hsp70 gene was downregulated (2.29-fold); whereas, Hsp27 gene was upregulated (1.16-fold) in G6, the group co-exposed with 96 h-LC50/10 As3+ with 8 ppm of MO in comparison with G3 (3.11-fold for Hsp70; 0.51-fold for Hsp27) after 96 h of exposure period. Thus, it can be inferred that the MO at its tested concentration can be effectively used to mitigate As3+ generated toxicities in C. punctatus.