Effects of Ag Nanoparticles on Growth and Fat Body Proteins in Silkworms (Bombyx mori)

Abstract

Ag nanoparticles (AgNPs), a widely used non-antibiotic, antibacterial material, have shown toxic and other potentially harmful effects in mammals. However, the deleterious effects of AgNPs on insects are still unknown. Here, we studied the effects of AgNPs on the model invertebrate organism Bombyx mori. After feeding silkworm larvae different concentrations of AgNPs, we evaluated the changes of B. mori body weights, survival rates, and proteomic differences. The results showed that low concentrations (<400 mg/L) of AgNPs promoted the growth and cocoon weights of B. mori. Although high concentrations (≥800 mg/L) of AgNPs also improved B. mori growth, they resulted in silkworm death. An analysis of fat body proteomic differences revealed 13 significant differences in fat body protein spots, nine of which exhibited significantly downregulated expression, while four showed significantly upregulated expression. Reverse transcription–polymerase chain reaction results showed that at an AgNP concentration of 1600 mg/L, the expression levels of seven proteins were similar to the transcription levels of their corresponding genes. Our results suggest that AgNPs lowered the resistance to oxidative stress, affected cell apoptosis, and induced cell necrosis by regulating related protein metabolism and metabolic pathways in B. mori.

Effect of feed supplementation with biosynthesized silver nanoparticles using leaf extract of Morus indica L. V1 on Bombyx mori L. (Lepidoptera: Bombycidae)

“…(2017) demonstrated that the feeding of silkworms with green synthesized AuNPs did not only improve the cocoon and silk but also enhanced the amount of silk protein, fibroin 75 . In a separate study, it was showed that AgNPs at concentrations lower than 400 µg/ml promoted the growth and cocoon weight, but higher doses (≥800 µg/ml) of AgNPs resulted in silkworm death 76 . In contrast to these findings, Wu et al .…”

Exposure to nanoceria impacts larval survival, life history traits and fecundity of Aedes aegypti

“…The cause(s) of this apparent growth arrest is unknown. Perhaps AgCNPs impact ecdysone receptor functions [ 64 , 65 ] and/or reactive oxygen species (ROS)-mediated signaling [ 66 ].…”

Investigating silk yield and morphological changes in silk fibres obtained from silkworms fed with Ag and/or $$\hbox {TiO}_{2}$$ nanoparticles

“…When compared to the reported studies [1,4,6,9,21] involving nanoparticle supplementations to their diet, our study is different from its kind where mixtures of nanoparticles (Ag and/or TiO 2 ) in low doses were given as dietary supplements to silkworms. The results of our study are encouraging as a recent study by Meng et al [21] pointed out that lowdoses of nanoparticles in feeding will help in growth and cocoon weights of silkworms effectively. This study with silkworms and nanoparticles attained cocoons with more silk % and silk fibres with reasonably high average diameter.…”

“…Therefore, it can be concluded that there is a significant variation in the uptake of Ag and Ti when silkworms are fed with similar concentrations of Ag and/or TiO 2 nanoparticles. It is certain that silkworms accept and excrete nanoparticles if given as feed supplement [6,9,21] and this amount may vary with the type of nanoparticles as detailed in our case.…”