Journal Article

Sublethal effects of malathion on behavior and hepatic gene expression of HSP70 and CYP1A in Persian Sturgeon (Acipenser persicus) fingerlings

Sattari, Masoud, Rahbar, Mina, Khara, Hossein, Noverian, Hamid Alaf, Ahmadnezhad, Mohaddeseh, Safari, Roghieh

2025

Overview

Malathion, an organophosphate pesticide widely used in agriculture, poses significant risks to aquatic ecosystems. This study investigated the sublethal effects of malathion on hepatic HSP70 and CYPIA gene expression in fingerling Persian sturgeon (Acipenser persicus). Fish were exposed to 0.05, 0.1, and 0.2 mg L-1 malathion (corresponding to sublethal fractions of the LC50) for 7 days. Liver samples were collected at 1, 2, 4, and 7 days post-exposure, and gene expression was quantified using real-time polymerase chain reaction (PCR). Behavioral responses and mortality were recorded. No mortality occurred in any group; however, fish exposed to 0.2 mg L-1 malathion exhibited reduced feeding, impaired swimming balance, and decreased activity, especially toward the end of exposure. HSP70 expression peaked on day 1 at the highest concentration (15.7-fold higher than the control) and then gradually declined. CYP1A expression showed a similar dose-dependent pattern, with the highest induction (19.29-fold) observed on day 4 in the 0.2 mg/L group. Heat map visualization confirmed temporal and dose-dependent expression dynamics. A significant positive correlation (r = 0.73, P<0.0001) between the expression levels of HSP70 and CYPIA suggested a coordinated stress response to malathion exposure. These results demonstrate malathion-induced modulation of oxidative stress and detoxification genes in Persian sturgeon, underscoring the utility of these molecular biomarkers for monitoring organophosphate pollution in aquatic species.

• Publisher: Iranian Society of Ichthyology
• Subject: Acipenser persicus / Agrochemicals / Aquatic ecosystems / Behavioural responses / Biological stress / Biomarkers / CYP1A protein / Cytochrome P450 / Detoxification / Exposure / Fingerlings / Fish / Freshwater fishes / Gene expression / Hsp70 protein / Liver / Malathion / Mortality / Mortality causes / Nucleotide sequence / Organophosphates / Organophosphorus pesticides / Oxidative stress / PCR / Pesticides / Polymerase chain reaction / Real time / Sturgeon / Sublethal effects / Swimming / Toxicity tests