Cellular identities in an unusual presentation of cyclopia in a chick embryo

In ovo exposure of F-ions and organo-fluoride insecticide (Bifenthrin) cause developmental anomalies of eye in chick embryos

Objective

The developmental abnormalities of the in-ovo exposure of Fluoride ions (F-ions) and Bifenthrin (BF) on the embryonic chick eye were investigated.

Materials and methods

165 fresh fertilized eggs of zero day and 40-50 g weight were divided into three groups (55 eggs each) on the basis of inter-vitelline treatment of eggs on zero day of study: 1) Control group (CG); 0.1 ml of 5 % DMSO aqueous solution 2),3) Fluoride group (FG), and Bifenthrin group (BFG); 0.01 mg/kg F-ions (from NaF) and 0.01 mg/kg BF in 0.1 ml of 5 % DMSO aqueous solution respectively. After incubation for 14 days at 37 ± 0.5 °C embryos were externalized. Eyes of each embryo were removed for micro-anatomical, micrometric and histopathological studies.

Results

The histological sections have shown denser and enlarged marginal mitotic region of the developing eye lenses in FG and BFG. In vertical sections of the eye lenses the nuclei of the crystalline cells in FG and BFG show a highly depressed bow shaped arrangement. Moreover, the nuclei of the core crystalline cells of the lens were apparently smaller in FG and BFG than CG. Out of the six anatomical layers of the retina the nuclear and the plexiform layers were highly enlarged in FG and BFG, similarly the three corneal cell layers (endothelial, parenchymal and epithelial) were enlarged in FG and BFG than CG. The morphometric, histometric and micrometric estimations also show significant variations in FG and BFG than CG.

Conclusion

The results indicate subtle developmental anomalies of the eyes attributable to the F-ions and BF exposure indicating their developmental neuro-optic disruption potentials. Results further revealed higher toxicity of BF as compared to F-ions.

In Vivo and In Vitro Cartilage Differentiation from Embryonic Epicardial Progenitor Cells

The presence of cartilage tissue in the embryonic and adult hearts of different vertebrate species is a well-recorded fact. However, while the embryonic neural crest has been historically considered as the main source of cardiac cartilage, recently reported results on the wide connective potential of epicardial lineage cells suggest they could also differentiate into chondrocytes. In this work, we describe the formation of cardiac cartilage clusters from proepicardial cells, both in vivo and in vitro. Our findings report, for the first time, cartilage formation from epicardial progenitor cells, and strongly support the concept of proepicardial cells as multipotent connective progenitors. These results are relevant to our understanding of cardiac cell complexity and the responses of cardiac connective tissues to pathologic stimuli.

Teratogenic and Neurotoxic Effects of n-Butanol on Zebrafish Development

In recent years, n-butanol, a type of alcohol, has been widely used from the chemical industry to the food industry. In this study, toxic effects of n-butanol's different concentrations (10, 50, 250, 500, 750, 1,000, and 1,250 mg/L) in Zebrafish Danio rerio embryos and larvae were investigated. For this purpose, Zebrafish embryos were exposed to n-butanol in acute semistatic applications. Teratogenic effects such as cardiac edema, scoliosis, lordosis, head development abnormality, yolk sac edema, and tail abnormality were determined at different time intervals (24, 48, 72, 96, and 120 h). Additionally, histopathological abnormalities such as vacuole formation in brain tissue and necrosis in liver tissue were observed at high doses (500, 750, and 1,000 mg/L) in all treatment groups at 96 h. It was determined that heart rate decreased at 48, 72, and 96 h due to an increase in concentration. In addition, alcohol-induced eye size reduction (microphthalmia) and single eye formation (cyclopia) are also among the effects observed in our research findings. In conclusion, n-butanol has been observed to cause intense neurotoxic, teratogenic, and cardiotoxic effects in Zebrafish embryos and larvae.