Analysis of mutants from a genetic screening reveals the control of intestine and liver development by many common genes in zebrafish

In silico and in vivo anti-angiogenic validation on ethanolic extract of Curcuma longa and curcumin compound in hepatocellular carcinoma through mitogen activated protein kinase expression in male and female wistar rats

Hepatocellular carcinoma (HCC) is the most frequent primary malignancy of the liver. The aim of this study is to evaluate the comparative in silico and in vivo ameliorative potential of the ethanolic extract of Curcuma longa (EECL) in male and female Wistar rats administered N-nitrosodiethylamine-induced hepatocellular carcinoma. The MAPK compound was obtained from a protein data bank (PDB ID: 7AUV) for molecular docking. One hundred and twenty Wistar rats, were randomly selected into twelve groups (n = 5): Group A received regular diets as a basal control; groups B to G were administered 100 mg/kg NDEA twice in two weeks; while groups C to E received 200 mg/kg, 400 mg/kg, and 600 mg/kg of EECL; group F was treated with 200 mg/kg pure curcumin; and group G received 100 mg/kg Sylibon-140. Group H received only 200 mg/kg pure curcumin, and group I received 200 mg/kg of dimethylsulfoxide (DMSO). Groups J, K, and L received 200 mg/kg, 400 mg/kg and 600 mg/kg of EECL. MAPK and AFP mRNA in Wistar rats administered NDEA were upregulated as compared to EECL groups. In conclusion, the in silico and in vitro study validates the mitigating role of ethanolic extract of Curcuma longa and pure curcumin.

Bisphenol C induces developmental defects in liver and intestine through mTOR signaling in zebrafish (Danio rerio)

Bisphenol A (BPA) was widely used in the plastic products and banned in infant food containers in many countries due to the environmental and biological toxicity. As a common substitute of BPA to manufacture products, Bisphenol C (BPC) is frequently detected in human samples like infants and toddlers' urine, indicating infants and young children are at risk of BPC exposure. However, the understanding of effects of BPC exposure on early development is limited. Herein, we evaluated the early developmental toxicity of BPC and studied the underlying mechanism in a zebrafish model. We found BPC exposure leading to liver and intestinal developmental defects in zebrafish, which occurred via disruption of GPER-AKT-mTOR-RPS6 pathway. Specifically, BPC downregulated phosphorylated and total levels of mTOR, which synergistically reduced the phosphorylation of RPS6, suppressing the translation of genes essential for cell proliferation in liver and intestine such as yap1 and tcf4. Collectively, our results not only observed clear toxicity of BPC during liver and intestinal development but also demonstrated the underlying mechanism of BPC-mediated defects via disrupting the GPER-AKT-mTOR-RPS6 pathway.

Large-scale forward genetic screening of zebrafish affecting thyroid development

The thyroid follicular cells originate from the foregut endoderm and elucidating which genes and signaling pathways regulate their development is crucial for understanding developmental disorders as well as diseases in adulthood. We exploited unique advantages of the zebrafish model to carry an ENU-based forward mutagenesis screen aiming at identifying genes involved in the development and function of the thyroid follicular cells. ENU is an excellent chemical mutagen due to its high mutation efficiency and an indiscriminate selection of genes. A total of 1606 F2 families from 36 ENU treated founders was raised and embryos from F3 generation were collected at 5dpf to perform the whole embryo in situ hybridization with a cocktail probe of thyroid marker thyroglobulin(tg), pituitary marker thyroid stimulating hormone (tshba) to determine the mutagenic phenotype. Among the 1606 F2 families, 112 F2 mutant families with normal development stages except for thyroid dysfunction were identified and divided into three different groups according to their phenotypic characteristics. Further studies of the mutants are likely to shed more insights into the molecular basis of both the thyroid development and function in the zebrafish and vertebrate.

Liver regeneration - mechanisms and models to clinical application

Liver regeneration has been studied for many decades and the mechanisms underlying regeneration of the normal liver following resection or moderate damage are well described. A large number of factors extrinsic (such as bile acids and circulating growth factors) and intrinsic to the liver interact to initiate and regulate liver regeneration. Less well understood, and more clinically relevant, are the factors at play when the abnormal liver is required to regenerate. Fatty liver disease, chronic scarring, prior chemotherapy and massive liver injury can all inhibit the normal programme of regeneration and can lead to liver failure. Understanding these mechanisms could enable the rational targeting of specific therapies to either reduce the factors inhibiting regeneration or directly stimulate liver regeneration. Although animal models of liver regeneration have been highly instructive, the clinical relevance of some models could be improved to bridge the gap between our in vivo model systems and the clinical situation. Likewise, modern imaging techniques such as spectroscopy will probably improve our understanding of whole-organ metabolism and how this predicts the liver's regenerative capacity. This Review describes briefly the mechanisms underpinning liver regeneration, the models used to study this process, and discusses areas in which failed or compromised liver regeneration is clinically relevant.