**Background**
The management of insect pests remains a critical challenge in agriculture and public health, necessitating the development of agents with high efficacy and low mammalian toxicity. Nicotinic acetylcholine receptors (nAChRs) are prototypical neurotransmitter ligand-gated ion channels in the insect nervous system, making them primary targets for the development of neurotoxic insecticides. Traditional chemical insecticides often face issues such as environmental persistence and the emergence of resistant pest populations. Consequently, there is a growing demand for biological alternatives that offer a broader action spectrum while maintaining an excellent environmental profile. In this context, we will introduce a biological neurotoxic insecticide – Spinosad.
**Definition**
Spinosad is a natural mixture of the pediculicidal tetracyclic macrolides spinosyn A and spinosyn D, produced via the fermentation of the soil actinomycete Saccharopolyspora spinosa. It functions as a biological neurotoxin that targets the nicotinic acetylcholine receptors (nAChRs) of the insect nervous system.
**In Vitro and In Vivo Studies**
According to the Spinosad description, this compound acts as an allosteric agonist of acetylcholine (Ach) by binding to nAChRs. Spinosad in vitro studies demonstrate its ability to activate these ligand-gated ion channels, leading to neuronal excitation. Regarding Spinosad In Vivo activity, a 0.9% concentration of the agent interferes with nAChRs in insects, producing prolonged hyperexcitation and subsequent neuromuscular fatigue, which results in the paralysis of lice. Notably, Spinosad is effective against both permethrin-susceptible and permethrin-resistant populations and exhibits ovicidal activity, killing both nits and adult lice. Furthermore, research on Oreochromis niloticus indicates that Spinosad induces oxidative effects in brain tissue by altering the GSH-related antioxidant system and Hsp70, specifically increasing levels of tGSH, GSH, GSSG, and Hsp70, while reducing the GSH/GSSG ratio and GPx activity. For researchers requiring specific Spinosad technical information, it is noted that the compound has a molecular weight of 1477.94 and a formula of C83H132N2O20. In conclusion, Spinosad is a potent biological insecticide with significant larvicidal and pediculicidal activity.
Keywords
Spinosad, 168316-95-8, nAChR, Nicotinic acetylcholine receptors, natural, fermentation, antioxidant, neuronal, insecticide, Inhibitor, inhibitor, inhibit
References
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