Assessment of the protective role of dietary rosemary extract against deltamethrin-induced neuroimmunity, apoptosis, and DNA damage in rainbow trout brain tissue (Oncorhynchus mykiss)

Abstract

Deltamethrin (DM), classified as a type II synthetic pyrethroid, is a potent insecticide that works by targeting the central nervous system of insects. It achieves this by affecting the function of voltage-sensitive sodium channels, which ultimately leads to increased sodium permeability in nerve membranes. This study explored the protective effects of dietary rosemary (Rosmarinus officinalis) extract [RE] against DM toxicity in rainbow trout’s brain tissue. The groups formed for the experiment were fed with commercial trout and RE added to commercial trout feed for 50 days. Then the DM toxicity was applied as follows: control group, 1 µg/L DM group, 1 µg/L DM group after feeding with 1% RE and 1 µg/L DM group after feeding with 3% RE. The neurotoxic effects such as oxidative stress (malondialdehyde [MDA]), antioxidant enzyme activities (catalase [CAT] and superoxide dismutase [SOD]), acetylcholinesterase (AChE) activity, immune system, specifically lymphocyte (Lym), total immunoglobulin (T. Ig), lysozyme, white blood cell (WBC), and cell death markers through caspase-3 and 8-hydroxy-2-deoxyguanosine (8-OHdG) were measured. DM increased malondialdehyde (MDA), caspase-3, and 8-OHdG levels and decreased AChE activity, lipid, protein, Lym, T. Ig, lysozyme, WBC, SOD, and CAT levels in the brain tissue compared with the control group. Conversely, diets containing 1% and 3% RE significantly increased antioxidant and innate immunity and significantly reduced oxidative stress, apoptosis and DNA damage compared to the DM group. In sum, the potential beneficial effect of natural therapies and 3% RE in particular can be used as a preventive, enhancing, effective and sustainable alternative against pharmaceutical treatments.

Keywords

• Fish
• rosemary
• deltamethrin
• apoptosis
• DNA damage
• immunity