Exploiting the Freshwater Shrimp Neocaridina denticulata as Aquatic Invertebrate Model to Evaluate Nontargeted Pesticide Induced Toxicity by Investigating Physiologic and Biochemical Parameters

Abstract

As a nicotinoid neurotoxic insecticide, imidacloprid (IMI) works by disrupting nerve transmission via nicotinic acetylcholine receptor (nAChR). Although IMI is specifically targeting insects, nontarget animals such as the freshwater shrimp, Neocaridina denticulata, could also be affected, thus causing adverse effects on the aquatic environment. To investigate IMI toxicity on nontarget organisms like N. denticulata, their physiology (locomotor activity, heartbeat, and gill ventilation) and biochemical factors (oxidative stress, energy metabolism) after IMI exposure were examined. IMI exposure at various concentrations (0.03125, 0.0625, 0.125, 0.25, 0.5, and 1 ppm) to shrimp after 24, 48, 72 h led to dramatic reduction of locomotor activity even at low concentrations. Meanwhile, IMI exposure after 92 h caused reduced heartbeat and gill ventilation at high concentrations. Biochemical assays were performed to investigate oxidative stress and energy metabolism. Interestingly, locomotion immobilization and cardiac activity were rescued after acetylcholine administration. Through molecular docking, IMI demonstrated high binding affinity to nAChR. Thus, locomotor activity and heartbeat in shrimp after IMI exposure may be caused by nAChR blockade and not alterations caused by oxidative stress and energy metabolism. To summarize, N. denticulata serves as an excellent and sensitive aquatic invertebrate model to conduct pesticide toxicity assays that encompass physiologic and biochemical examinations.

Locomotor behavior of Neocaridina palmata: a study with leachates from UV-weathered microplastics

“…We applied similar test variables in terms of acclimatization period ( Chen et al, 2020 ; Wang et al, 2020 ), recording time ( Wang et al, 2020 ) and replicate number per treatment as other studies ( Gerhardt, 2020 ; Xu et al, 2020 ). It is noteworthy that the test variables for the assessment of the swimming activity can vary greatly ( Faimali et al, 2017 ; Siregar et al, 2021 ; Sun et al, 2021 ). Since we have analyzed several recording lengths in a preliminary study and detected no differences between the groups ( Fig.…”

“…We used the atyid shrimp Neocaridina palmata and recorded the moved distance and frozen events during the exposure to enriched leachable chemicals from MPs ≤1 mm. Neocaridina is easy to culture and known to be sensitive to environmental pollutants ( Siregar et al, 2021 ) and therefore is frequently used as a model organism ( Mykles et al, 2016 ). The sublethal endpoints were analyzed with the open-source software ToxTrac ( Rodriguez et al, 2018 ).…”

Physiological Effects of Neonicotinoid Insecticides on Non-Target Aquatic Animals—An Updated Review

“…During our investigation on the toxicity of imidacloprid on non-target organisms such as Neocaridina denticulata, imidacloprid demonstrated high binding affinity to nAChR through a molecular docking simulation study [42]. The acetylcholine binding protein (AChBP) from the snail Lymnaea stagnalis was used for this purpose since it is considered a surrogate marker of the ligand-binding domain in nAChRs for loops A-F, which are highly conserved.…”

“…The relatively strong interaction was due to conventional hydrogen bonding between the nitrogen of the pyridine moiety in imidacloprid with Trp143 and amidine N-nitro with the phenolic residue of Tyr192. In contrast, acetylcholine interacted via weak van der Waals with Trp143 of nAChR [42]. A summary of common neonicotinoids their mode of action and model organisms (invertebrates and vertebrates) is depicted in Figure 1.…”

“…In our previous study, we successfully demonstrated the adverse effect of imidacloprid on non-target organisms of freshwater shrimp (Neocaridina denticuata) as a new aquatic invertebrate model to test neonicotinoid toxicity [42]. Freshwater shrimp were exposed to imidacloprid depicted immobilization, reduction in heart rate, decrease in gill ventilation and death.…”