Adverse Effects from Clenbuterol and Ractopamine on Nematode Caenorhabditis elegans and the Underlying Mechanism

Abstract

In the present study, we used Caenorhabditis elegans assay system to investigate in vivo toxicity from clentuberol and ractopamine and the possible underlying mechanism. Both acute and prolonged exposures to clentuberol or ractopamine decreased brood size and locomotion behavior, and induced intestinal autofluorescence and reactive oxygen species (ROS) production. Although acute exposure to the examined concentrations of clentuberol or ractopamine did not induce lethality, prolonged exposure to 10 µg/L of clentuberol and ractopamine reduced lifespan. At relatively high concentrations, ractopamine exhibited more severe toxicity than clentuberol on nematodes. Overexpression of sod-2 gene encoding a Mn-SOD to prevent induction of oxidative stress effectively inhibited toxicity from clentuberol or ractopamine. Besides oxidative stress, we found that clentuberol might reduce lifespan through influencing insulin/IGF signaling pathway; however, ractopamine might reduce lifespan through affecting both insulin/IGF signaling pathway and TOR signaling pathway. Ractopamine more severely decreased expression levels of daf-16, sgk-1, skn-1, and aak-2 genes than clentuberol, and increased expression levels of daf-2 and age-1 genes at the examined concentration. Therefore, the C. elegans assay system may be useful for assessing the possible toxicity from weight loss agents, and clentuberol and ractopamine may induce toxicity through different molecular mechanisms.

Mutagenicity and DNA-damaging potential of clenbuterol and its metabolite 4-amino-3,5-dichlorobenzoic acid in vitro

“…Taken together, the pro-oxidative effect of clenbuterol could be related to the metabolites formed during the 72-h treatment. These results are in accordance with those of Zhuang et al (2014), although it should be mentioned that the latter authors conducted their experiments on nematodes in vivo.…”

“…Data on clenbuterol's pro-oxidative powers are scarce. Zhuang et al (2014) reported that acute exposure to clenbuterol applied in concentrations of 0.01-0.1 ng/ml, as well as a prolonged exposure to the same substance applied in concentrations of 0.01-0.1 ng/ml, did not induce significant intestinal autofluorescence in nematodes. Contrary, acute exposure to 5 ng/ml clenbuterol caused significant auto-fluorescence.…”

“…It is also often illegally used as a feed additive to improve production performance and carcass composition (Zhuang et al, 2014). Although, it is obvious that this compound is in massive use (legal or illegal), little data concerning its toxicity and mutagenic/ genotoxic potential are available.…”

Adverse effects of coal combustion related fine particulate matter (PM 2.5 ) on nematode Caenorhabditis elegans

“…The methods were performed as described previously (Wu et al, 2014b;Zhuang et al, 2014). Nematodes were judged to be dead if they did not respond to a stimulus using a small metal wire.…”

The Use of the Nematode Caenorhabditis elegans to Evaluate the Adverse Effects of Epoxiconazole Exposure on Spermatogenesis

“…Epoxiconazole was dissolved in DMSO (Sigma-Aldrich, St. Louis, MO, USA) and M9 buffer (2.5 g of NaCl, 3.0 g of Na 2 HPO 4 and 1.5 g of KH 2 PO 4 ) to prepare the working solution at final concentrations of 0.1, 1.0 and 10.0 μg/L. Epoxiconazole exposures were performed for 48 h in 24-well culture plates at 20 °C according to a previous description [24]. The solvent controls were prepared in the same way.…”