c-myb is involved in CML progression and is a therapeutic target in the zebrafish CML model

Background:Despite the success of tyrosine kinase inhibitors in chronic myeloid leukemia(CML)therapy,CML still faces the challenges of drug resistance and progression to blast crisis.Twenty-five percent of patients have imatinib resistance and treatment difficulties due to heterogeneity after progression,but little is known about the mechanism.A key transcription factor in hematopoiesis,MYB,has been reported to increase abnormally in several types of aggressive blood disorders including CML.Methods:This study used a zebrafish model to explore the relationship between BCR/ABL1 and c-myb in CML progression.A CML zebrafish model was crossed with a c-myb hyperactivity transgenic line.Results:It was found that both exogenous BCR/ABL1 and c-myb could up-regulate the expression of neutrophil-related genes.More seriously,neutrophil accumulation was observed when BCR/ABL1 was combined with c-myb overexpression.Further studies showed that c-myb may be one of the downstream targets of BCR/ABL1 and the effect of BCR/ABL1 on neutrophils was c-myb dependent.Taking advantage of this inheritable in vivo model,it was shown that a combination of imatinib and flavopiridol,a cyclin-dependent kinase inhibitor targeting MYB,could more effectively alleviate the aggressive phenotype of the double transgene line.Conclusion:In summary,this study suggests that c-myb acts downstream of BCR/ABL1 and is involved in CML progression and is therefore a risk factor and a valuable target for the treatment of CML progression.The model used in the study could be helpful in high-throughput drug screening in CML transformation.

Animal models of amyotrophic lateral sclerosis： a comparison of model validity

Animal models are necessary to investigate the pathogenic features underlying motor neuron degeneration and for therapeutic development in amyotrophic lateral sclerosis（ALS）. Measures of model validity allow for a critical interpretation of results from each model and caution from over-interpretation of experimental models. Face and construct validity refer to the similarity in phenotype and the proposed causal factor to the human disease, respectively. More recently developed models are restricted by limited phenotype characterization, yet new models hold promise for novel disease insights, thus highlighting their importance. In this article, we evaluate the features of face and construct validity of our new zebrafish model of environmentally-induced motor neuron degeneration and discuss this in the context of current environmental and genetic ALS models, including C9 orf72, mutant Cu/Zn superoxide dismutase 1 and TAR DNA-binding protein 43 mouse and zebrafish models. In this mini-review, we discuss the pros and cons to validity criteria in each model. Our zebrafish model of environmentally-induced motor neuron degeneration displays convincing features of face validity with many hallmarks of ALS-like features, and weakness in construct validity. However, the value of this model may lie in its potential to be more representative of the pathogenic features underlying sporadic ALS cases, where environmental factors may be more likely to be involved in disease etiology than single dominant gene mutations. It may be necessary to compare findings between different strains and species modeling specific genes or environmental factors to confirm findings from ALS animal models and tease out arbitrary strain-and overexpression-specific effects.

Novel MIP gene mutation causes autosomal-dominant congenital cataract

●AIM:To identify disease-causative mutations in families with congenital cataract.●METHODS:Two Chinese families with autosomaldominant congenital cataract(ADCC)were recruited and underwent comprehensive eye examinations.Gene panel next-generation sequencing of common pathogenic genes of congenital cataract was performed in the proband of each family.Sanger sequencing was used to valid the candidate gene mutations and sequence the other family members for co-segregation analysis.The effect of sequence changes on protein structure and function was predicted through bioinformatics analysis.Major intrinsic protein(MIP)-wildtype and MIP-G29R plasmids were constructed and microinjected into zebrafish single-cell stage embryos.Zebrafish embryonic lens phenotypes were screened using confocal microscopy.●RESULTS:A novel heterozygous mutation(c.85G>A;p.G29R)in the MIP gene was identified in the proband of one family.A known heterozygous mutation(c.97C>T;p.R33C;rs864309693)in MIP was found in the proband of another family.In-silico prediction indicated that the novel mutation might affect the MIP protein function.Zebrafish embryonic lens was uniformly transparent in both wild-type PCS2+MIP and mutant PCS2+MIP.●CONCLUSION:Two missense mutations in the MIP gene in Chinese cataract families are identified,and one of which is novel.These findings expand the genetic spectrum of MIP mutations associated with cataracts.The functional studies suggest that the novel MIP mutation might not be a gain-of-function but a loss-of-function mutation.

Analysis of the key networks,metabolic pathways,and regulation substances of hypoxia based on the omics and zebrafish model

OBJECTIVE Hypoxia is associated with many complicated pathophysiological and biochemical processes that integrated and regulated via the key gene,protein and endogenous metabolite levels.Up to date,the exact molecular mechanism of hypoxia still remains unclear.In this work,we further explore the molecular mechanism of hypoxia and adaption to attenuate the damage in zebrafish model that have potential to resist hypoxic environment.METHODS The hypoxic zebrafish model was established in different concentration of oxygen with 3%,5%,10%,21%in water.The brain tissue was separated and the RNA-seq was used to identify the differentially expressed genes.The related endogenous metabolites profiles were obtained by LC-HDMS,and the multivariate statistics was applied to discover the important metabolites candidates in hypoxic zebrafish.The candidates were searched in HMDB,KEGG and Lipid Maps databases.RESULTS The zebrafish hypoxic model was successfully constructed via the different concentration of oxygen,temperature and hypoxic time.The activities of the related hypoxic metabolic enzymes and factors including HIF-1a,actate dehydrogenase(LDH)and citrate synthase(CS)were evaluated.Significant differences(P<0.05 and fold change>2)in the expression of 422 genes were observed between the normal and 3% hypoxic model.Among them,201 genes increased depended on the lower concentration of oxygen.53 metabolites were identified that had significant difference between the hypoxia and control groups(P<0.05,fold change>1.5 and VIP>1.5).The ten key metabolites were increased gradually while six compounds were decreased.The endogenous hypoxic metabolites of phenylalanine,D-glucosamine-6P and several important lipids with the relevant hub genes had similar change in hypoxic model.In addition,the metabolic pathways of phenylalanine,glutamine and glycolipid were influenced in both the levels of genes and metabolites.CONCLUSION The up-regulation of phenylalanine,D-glucosamine-6P and lipid may have further understanding of protective effect in hypoxia.Our data provided an insight to further reveal the hypoxia and adaptation mechanism.

Efficacy Evaluation of Bifida Ferment Lysate in Cosmetic

By constructing a cell repair model after photodamage, we evaluated the photoresistance of FermentDFL, a lysate of Bifidus yeast fermentation products, of human immortalized keratinocytes(HaCaT) and human skin fibroblasts(HDF) under UVB and UVA irradiation. The experimental data show that when human cells are damaged by light, Ferment-DFL with a concentration of 5% and 2% can significantly increase the level of cell viability, reduce the content of ROS reactive oxygen species in cells, and promote the secretion of type I collagen. The regeneration experiment evaluates the repair effect of Ferment-DFL, a lysate of two fission yeast fermentation products. At a concentration of 6%, after 48 h, the repairing promotion rate of zebrafish embryo tail fin reaches 15%, which can significantly promote the regeneration of zebrafish embryo tail fin.Promotes repairing effect.

(+)/(-)-Gerbeloid A,a pair of unprecedented coumarin-based polycyclic meroterpenoid enantiomers from Gerbera piloselloides:Structural elucidation,semi-synthesis,and lipid-lowering activity

A pair of coumarin-based polycyclic meroterpenoid enantiomers(+)/(-)-gerbeloid A[(+)-1a and(-)-1b]were isolated from the medicinal plant Gerbera piloselloides,which have a unique caged oxatricyclo[4.2.2.0^(3,8)]decene scaffold.Their planar and three-dimensional structures were exhaustively characterized by comprehensive spectroscopic data and X-ray diffraction analysis.Guided by the hypothetical biosynthetic pathway,the biomimetic synthesis of racemic 1 was achieved using 4-hydroxy-5-methylcoumarin and citral as the starting material via oxa-6πelectrocyclization and intramolecular[2+2]photocycloaddition.Subsequently,the results of the biological activity assay demonstrated that both(+)-1a and(-)-1b exhibited potent lipid-lowering effects in 3T3-L1 adipocytes and the high-fat diet zebrafish model.Notably,the lipid-lowering activity of(+)-1a is better than that of(-)-1b at the same concentration,and molecular mechanism study has shown that(+)-1a and(-)-1b impairs adipocyte differentiation and stimulate lipolysis by regulating C/EBPα/PPARγsignaling and Perilipin signaling in vitro and in vivo.Our findings provide a promising drug model molecule for the treatment of obesity.

Establishment of Multi-Site Infection Model in Zebrafish Larvae for Studying Staphylococcus aureus Infectious Disease

Zebrafish（Danio rerio） is an ideal model for studying the mechanism of infectious disease and the interaction between host and pathogen.As a teleost,zebrafish has developed a complete immune system which is similar to mammals.Moreover,the easy acquirement of large amounts of transparent embryos makes it a good candidate for gene manipulation and drug screening.In a zebrafish infection model,all of the site,timing,and dose of the bacteria microinjection into the embryo are important factors that determine the bacterial infection of host.Here,we established a multi-site infection model in zebrafish larvae of 36 hours post-fertilization（hpf） by micro-injecting wild-type or GFP-expressing Staphylococcus aereus（5.aureus） with gradient burdens into different embryo sites including the pericardial cavity（PC）,eye,the fourth hindbrain ventricle（4V）,yolk circulation valley（YCV）,caudal vein（CV）,yolk body（YB）,and Duct of Cuvier（DC） to resemble human infectious disease.With the combination of GFP-expressing S.aureus and transgenic zebrafish Tg（corola：eGFP;lyz：Dsred） and Tg（lyz：Dsred） lines whose macrophages or neutrophils are fluorescent labeled,we observed the dynamic process of bacterial infection by in vivo multicolored confocal fluorescence imaging.Analyses of zebrafish embryo survival, bacterial proliferation and myeloid cells phagocytosis show that the site- and dose-dependent differences exist in infection of different bacterial entry routes.This work provides a consideration for the future study of pathogenesis and host resistance through selection of multi-site infection model.More interaction mechanisms between pathogenic bacteria virulence factors and the immune responses of zebrafish could be determined through zebrafish multi-site infection model.

Targeting lactate dehydrogenase A (LDHA) exerts antileukemic effects on T-cell acute lymphoblastic leukemia

Background:T-cell acute lymphoblastic leukemia(T-ALL)is an uncommon and aggressive subtype of acute lymphoblastic leukemia(ALL).In the serum of T-ALL patients,the activity of lactate dehydrogenase A(LDHA)is increased.We proposed that targeting LDHA may be a potential strategy to improve T-ALL outcomes.The current study was conducted to investigate the antileukemic effect of LDHA gene-targeting treatment on T-ALL and the underlying molecular mechanism.Methods:Primary T-ALL cell lines Jurkat and DU528 were treated with the LDH inhibitor oxamate.MTT,colony formation,apoptosis,and cell cycle assays were performed to investigate the effects of oxamate on T-ALL cells.Quantitative real-time PCR(qPCR)and Western blotting analyses were applied to determine the related signaling pathways.A mitochondrial reactive oxygen species(ROS)assay was performed to evaluate ROS production after T-ALL cells were treated with oxamate.A T-ALL transgenic zebrafish model with LDHA gene knockdown was established using CRISPR/Cas9 gene-editing technology,and then TUNEL,Western blotting,and T-ALL tumor progression analyses were conducted to investigate the effects of LDHA gene knockdown on T-ALL transgenic zebrafish.Results:Oxamate significantly inhibited proliferation and induced apoptosis of Jurkat and DU528 cells.It also arrested Jurkat and DU528 cells in G0/G1 phase and stimulated ROS production(all P<0.001).Blocking LDHA significantly decreased the gene and protein expression of c-Myc,as well as the levels of phosphorylated serine/threonine kinase(AKT)and glycogen synthase kinase 3 beta(GSK-3β)in the phosphatidylinositol 3′-kinase(PI3K)signaling pathway.LDHA gene knockdown delayed disease progression and down-regulated c-Myc mRNA and protein expression in T-ALL transgenic zebrafish.Conclusion:Targeting LDHA exerted an antileukemic effect on T-ALL,representing a potential strategy for T-ALL treatment.