Histopathological Profile of Obese Zebrafish Liver after Administration of Red Spinach (Amaranthus tricolor L.)

Aims: Obesity is a non-communicable disease whose prevalence continues to increase every year throughout the world. Obesity contributes to the emergence of several diseases such as type-2 diabetes mellitus, hypertension, cardiovascular disorders, cancer, and non-alcoholic fatty liver. A number of studies report that natural ingredients have the potential to be used as a treatment for obesity while reducing a fatty liver. The aim of this research is to evaluate the activity of red spinach ethanol extract in reducing the accumulation of fatty liver in diet-induced obese zebrafish based on its histopathological profile. Methodology: Zebrafish must be adapted for 2 weeks. After 2 weeks, the zebrafish were divided into 6 groups which included: the normal group (or negative control); the obesity group (positive control group); the standard drug (orlistat with dose 4.5 µg/ml); the EERS group (dose of 50 µg/ml); the EERS group (dose of 100 µg/ml); and the EERS group (dose of 200 µg/ml). For a period of 4 weeks, the normal group received a standard diet. A positive control group received Artemia. The treated group received Artemia which was combined with the administration of red spinach (preventive method). The obese group and extract-treated group were given 60 mg/group/fish in the experimental diet. Results: The results showed that EERS at a dose of 100 µg/ml did not show any fatty liver based on their histopathological profile. The EERS dose of 200 µg/ml is more effective in reducing fatty liver when compared to doses of 50 µg/ml and 100 µg/ml on obese zebrafish. Conclusion: Based on the results of the study, it can be concluded that EERS is very prospective for further research and development as a drug for treating obesity and reducing fatty liver.

Construction of fluorescent transgenic zebrafish Tg (ttn.2: EGFP) / 生物工程学报

In order to develop a transgenic zebrafish line with green fluorescent protein (enhanced green fluorescent protein, EGFP) expressed specifically in muscle and heart, the recombinant expression vector constructed using the zebrafish ttn.2 gene promoter fragment and EGFP gene coding sequence and the capped mRNA of Tol2 transposase were co-injected into the zebrafish 1-cell stage embryos. The stable genetic Tg (ttn.2: EGFP) transgenic zebrafish line was successfully developed by fluorescence detection, followed by genetic hybridization screening and molecular identification. Fluorescence signals and whole-mount in situ hybridization showed that EGFP expression was located in muscle and heart, the specificity of which was consistent with the expression of ttn.2 mRNA. Inverse PCR showed that EGFP was integrated into chromosomes 4 and 11 of zebrafish in No. 33 transgenic line, while integrated into chromosome 1 in No. 34 transgenic line. The successful construction of this fluorescent transgenic zebrafish line, Tg (ttn.2: EGFP), laid a foundation for the research of muscle and heart development and related diseases. In addition, the transgenic zebrafish lines with strong green fluorescence can also be used as a new ornamental fish.

Down-regulation of complement genes in lipopolysaccharide-challenged zebrafish (Danio rerio) larvae exposed to Indonesian propolis / Regulação negativa dos genes do complemento em larvas de peixe-zebra (Danio rerio) desafiadas com lipopolissacarídeo expostas à própolis indonésia

Abstract Although propolis has been reported for having anti-inflammatory activities, its effects on complement system has not been much studied. This research was conducted to find out the effects of Indonesian propolis on the expression levels of C3, C1r/s, Bf, MBL, and C6 in zebrafish larvae which were induced by lipopolysaccharide (LPS). Counting of macrophages migrating to yolk sac and liver histology were carried out. Larvae were divided into four groups: CON (cultured in E3 medium only), LPS (cultured in a medium containing 0.5 μg/L LPS), LPSIBU (cultured in a medium containing LPS, and then treated with 100 μg/L ibuprofen for 24 hours), and LPSPRO (cultured in a medium containing LPS, and then immersed in 14,000 μg/L propolis for 24 hours) groups. The results showed that complement gene expression in larvae from the LPSIBU and LPSPRO groups were generally lower than in larvae from the LPS group. The number of macrophage migrations to the yolk in the LPSPRO group was also lower than in the LPS group. Histological structure of liver in all groups were considered normal. This study shows that Indonesian propolis has the potential to be used as an alternative to the substitution of NSAIDs.

Resumo Embora a própolis tenha sido relatada por ter atividade anti-inflamatória, seus efeitos no sistema complemento, uma parte do sistema imunológico inato, não foram muito estudados. Esta pesquisa foi conduzida para descobrir os efeitos da própolis da Indonésia nos níveis de expressão de C3, C1r/s, Bf, MBL e C6 em larvas de peixe-zebra induzidas por lipopolissacarídeo (LPS). Foram realizadas contagens de macrófagos que migram para o saco vitelino e histologia do fígado. As larvas foram divididas em quatro grupos: CON (cultivadas apenas em meio E3), LPS (cultivadas em meio contendo 0,5 μg/L de LPS), LPSIBU (cultivadas em meio contendo LPS e, em seguida, tratadas com 100 μg/L de ibuprofeno por 24 horas) e LPSPRO (cultivado em meio contendo LPS, e então imerso em própolis 14,000 μg/L por 24 horas). Os resultados mostraram que a expressão do gene do complemento em larvas dos grupos LPSIBU e LPSPRO foi geralmente menor que em larvas do grupo LPS. O número de migrações de macrófagos para a gema no grupo LPSPRO também foi menor que no grupo LPS. A estrutura histológica do fígado em todos os grupos foi considerada normal. Este estudo mostra que a própolis indonésia tem potencial para ser utilizada como alternativa na substituição dos AINEs (anti-inflamatórios não esteroides).

The interaction between polyphyllin I and SQLE protein induces hepatotoxicity through SREBP-2/HMGCR/SQLE/LSS pathway / 药物分析学报

Polyphyllin Ⅰ(PPⅠ)and polyphyllin Ⅱ(PⅡ)are the main active substances in the Paris polyphylla.However,liver toxicity of these compounds has impeded their clinical application and the potential hepatotoxicity mechanisms remain to be elucidated.In this work,we found that PPⅠ and PⅡ exposure could induce significant hepatotoxicity in human liver cell line L-02 and zebrafish in a dose-dependent manner.The results of the proteomic analysis in L-02 cells and transcriptome in zebrafish indicated that the hepa-totoxicity of PPⅡ and PⅡwas associated with the cholesterol biosynthetic pathway disorders,which were alleviated by the cholesterol biosynthesis inhibitor lovastatin.Additionally,3-hydroxy-3-methy-lglutaryl CoA reductase(HMGCR)and squalene epoxidase(SQLE),the two rate-limiting enzymes in the choles-terol synthesis,selected as the potential targets,were confirmed by the molecular docking,the over-expression,and knockdown of HMGCR or SQLE with siRNA.Finally,the pull-down and surface plasmon resonance technology revealed that PPⅠ could directly bind with SQLE but not with HMGCR.Collectively,these data demonstrated that PPⅠ-induced hepatotoxicity resulted from the direct binding with SQLE protein and impaired the sterol-regulatory element binding protein 2/HMGCR/SQLE/lanosterol synthase pathways,thus disturbing the cholesterol biosynthesis pathway.The findings of this research can contribute to a better understanding of the key role of SQLE as a potential target in drug-induced hepatotoxicity and provide a therapeutic strategy for the prevention of drug toxic effects with similar structures in the future.

Zebrafish ambra1b knockout reveals a novel role for Ambra1 in primordial germ cells survival, sex differentiation and reproduction

BACKGROUND: AMBRA1 is an intrinsically disordered protein, working as a scaffold molecule to coordinate, by protein-protein interaction, many cellular processes, including autophagy, mitophagy, apoptosis and cell cycle progression. The zebrafish genome contains two ambra1 paralogous genes (a and b), both involved in development and expressed at high levels in the gonads. Characterization of the zebrafish paralogous genes mutant lines generated by CRISPR/Cas9 approach showed that ambra1b knockout leads to an all-male population. RESULTS: We demonstrated that the silencing of the ambra1b gene determines a reduction of primordial germ cells (PGCs), a condition that, in the zebrafish, leads to the development of all-male progeny. PGC reduction was confirmed by knockdown experiments and rescued by injection of ambra1b and human AMBRA1 mRNAs, but not ambra1a mRNA. Moreover, PGC loss was not rescued by injection with human AMBRA1 mRNA mutated in the CUL4-DDB1 binding region, thus suggesting that interaction with this complex is involved in PGC protection from loss. Results from zebrafish embryos injected with murine Stat3 mRNA and stat3 morpholino suggest that Ambra1b could indirectly regulate this protein through CUL4-DDB1 interaction. According to this, Ambra1+/- mice showed a reduced Stat3 expression in the ovary together with a low number of antral follicles and an increase of atretic follicles, indicating a function of Ambra1 in the ovary of mammals as well. Moreover, in agreement with the high expression of these genes in the testis and ovary, we found significant impairment of the reproductive process and pathological alterations, including tumors, mainly limited to the gonads. CONCLUSIONS: By exploiting ambra1a and ambra1b knockout zebrafish lines, we prove the sub-functionalization between the two paralogous zebrafish genes and uncover a novel function of Ambra1 in the protection from excessive PGC loss, which seems to require binding with the CUL4-DDB1 complex. Both genes seem to play a role in the regulation of reproductive physiology.

Study on Mechanism of Action of Matrine in Treatment of Inflammatory Bowel Disease Based on Zebrafish Model and Network Pharmacology / 中国实验方剂学杂志

ObjectiveTo study the mechanism of matrine in the treatment of inflammatory bowel disease （IBD） based on the zebrafish model and network pharmacology. MethodThe IBD model of zebrafish was established using 2，4，6-trinitro-benzenesulfonicacid （TNBS）， and the intestinal phagocytic function， goblet cell secretion， and neutrophil aggregation were evaluated using neutral red staining， alcian blue staining， and neutrophil number changes. Changes in tumor necrosis factor （TNF）-α and cholecystokinin （CCK） content in zebrafish were determined by using relevant reagent kits. Network pharmacology and molecular docking techniques were used to predict the potential mechanism of matrine in the treatment of IBD. Gene expression of relevant targets was verified through Real-time polymerase chain reaction （Real-time PCR）. ResultCompared with the model group， the matrine administration group can increase the neutral red staining area in a dose-dependent manner and improve intestinal phagocytic function（P<0.05，P<0.01）. It can reduce the staining area of alcian blue and affect the secretion of intestinal goblet cells（P<0.01）. It can reduce the number of neutrophil granulocytes， relieve its aggregation， significantly reduce TNF-α content（P<0.01）， and increase the CCK content. Network pharmacology analysis identifies 28 potential targets for matrine in the treatment of IBD. The top five targets by protein-protein interaction （PPI） network analysis are CHRNA7， DRD1， CHRNA4， SLC6A3， and GRM5. The Kyoto encyclopedia of genes and genomes （KEGG） results show that the treatment of IBD with matrine may be related to neuroactive ligand-receptor interaction， cholinergic synapse， and neutrophil extracellular trap formation. Real-time PCR results show that matrine can affect the expression level of related target genes. Conclusionmatrine has a certain therapeutic effect on IBD and can affect the inflammatory response of IBD. Its therapeutic effect may be related to neuroactive ligand-receptor interaction and other pathways.

Down-regulation of complement genes in lipopolysaccharidechallenged zebrafish (Danio rerio) larvae exposed to Indonesian propolis / Regulação negativa dos genes do complemento em larvas de peixe-zebra (Danio rerio) desafiadas com lipopolissacarídeo expostas à própolis indonésia

Although propolis has been reported for having anti-inflammatory activities, its effects on complement system has not been much studied. This research was conducted to find out the effects of Indonesian propolis on the expression levels of C3, C1r/s, Bf, MBL, and C6 in zebrafish larvae which were induced by lipopolysaccharide (LPS). Counting of macrophages migrating to yolk sac and liver histology were carried out. Larvae were divided into four groups: CON (cultured in E3 medium only), LPS (cultured in a medium containing 0.5 μg/L LPS), LPSIBU (cultured in a medium containing LPS, and then treated with 100 μg/L ibuprofen for 24 hours), and LPSPRO (cultured in a medium containing LPS, and then immersed in 14,000 μg/L propolis for 24 hours) groups. The results showed that complement gene expression in larvae from the LPSIBU and LPSPRO groups were generally lower than in larvae from the LPS group. The number of macrophage migrations to the yolk in the LPSPRO group was also lower than in the LPS group. Histological structure of liver in all groups were considered normal. This study shows that Indonesian propolis has the potential to be used as an alternative to the substitution of NSAIDs.

Embora a própolis tenha sido relatada por ter atividade anti-inflamatória, seus efeitos no sistema complemento, uma parte do sistema imunológico inato, não foram muito estudados. Esta pesquisa foi conduzida para descobrir os efeitos da própolis da Indonésia nos níveis de expressão de C3, C1r/s, Bf, MBL e C6 em larvas de peixe-zebra induzidas por lipopolissacarídeo (LPS). Foram realizadas contagens de macrófagos que migram para o saco vitelino e histologia do fígado. As larvas foram divididas em quatro grupos: CON (cultivadas apenas em meio E3), LPS (cultivadas em meio contendo 0,5 μg/L de LPS), LPSIBU (cultivadas em meio contendo LPS e, em seguida, tratadas com 100 μg/L de ibuprofeno por 24 horas) e LPSPRO (cultivado em meio contendo LPS, e então imerso em própolis 14,000 μg/L por 24 horas). Os resultados mostraram que a expressão do gene do complemento em larvas dos grupos LPSIBU e LPSPRO foi geralmente menor que em larvas do grupo LPS. O número de migrações de macrófagos para a gema no grupo LPSPRO também foi menor que no grupo LPS. A estrutura histológica do fígado em todos os grupos foi considerada normal. Este estudo mostra que a própolis indonésia tem potencial para ser utilizada como alternativa na substituição dos AINEs (anti-inflamatórios não esteroides).

Down-regulation of complement genes in lipopolysaccharide-challenged zebrafish (Danio rerio) larvae exposed to Indonesian propolis

Abstract Although propolis has been reported for having anti-inflammatory activities, its effects on complement system has not been much studied. This research was conducted to find out the effects of Indonesian propolis on the expression levels of C3, C1r/s, Bf, MBL, and C6 in zebrafish larvae which were induced by lipopolysaccharide (LPS). Counting of macrophages migrating to yolk sac and liver histology were carried out. Larvae were divided into four groups: CON (cultured in E3 medium only), LPS (cultured in a medium containing 0.5 g/L LPS), LPSIBU (cultured in a medium containing LPS, and then treated with 100 g/L ibuprofen for 24 hours), and LPSPRO (cultured in a medium containing LPS, and then immersed in 14,000 g/L propolis for 24 hours) groups. The results showed that complement gene expression in larvae from the LPSIBU and LPSPRO groups were generally lower than in larvae from the LPS group. The number of macrophage migrations to the yolk in the LPSPRO group was also lower than in the LPS group. Histological structure of liver in all groups were considered normal. This study shows that Indonesian propolis has the potential to be used as an alternative to the substitution of NSAIDs.

Resumo Embora a própolis tenha sido relatada por ter atividade anti-inflamatória, seus efeitos no sistema complemento, uma parte do sistema imunológico inato, não foram muito estudados. Esta pesquisa foi conduzida para descobrir os efeitos da própolis da Indonésia nos níveis de expressão de C3, C1r/s, Bf, MBL e C6 em larvas de peixe-zebra induzidas por lipopolissacarídeo (LPS). Foram realizadas contagens de macrófagos que migram para o saco vitelino e histologia do fígado. As larvas foram divididas em quatro grupos: CON (cultivadas apenas em meio E3), LPS (cultivadas em meio contendo 0,5 g/L de LPS), LPSIBU (cultivadas em meio contendo LPS e, em seguida, tratadas com 100 g/L de ibuprofeno por 24 horas) e LPSPRO (cultivado em meio contendo LPS, e então imerso em própolis 14,000 g/L por 24 horas). Os resultados mostraram que a expressão do gene do complemento em larvas dos grupos LPSIBU e LPSPRO foi geralmente menor que em larvas do grupo LPS. O número de migrações de macrófagos para a gema no grupo LPSPRO também foi menor que no grupo LPS. A estrutura histológica do fígado em todos os grupos foi considerada normal. Este estudo mostra que a própolis indonésia tem potencial para ser utilizada como alternativa na substituição dos AINEs (anti-inflamatórios não esteroides).

Exploring the key anti-fatigue components of American ginseng based on metabolomics and zebrafish models / 药学学报

The aim of this paper is to explore the key anti-fatigue active components in the saponin-like composition of American ginseng. The anti-fatigue activity of western ginseng samples was evaluated using a zebrafish model; metabolomics techniques were used to identify the main saponins in western ginseng from different origins; the active substances and relevant targets of the anti-fatigue effect of western ginseng were initially screened by constructing a PPI protein interaction network between western ginseng saponins and disease targets, and the key active ingredients were screened using a molecular docking method; finally, the anti-fatigue activity of the key active ingredients was evaluated using a zebrafish, animal experiment was approved by the Ethics Committee of Shandong Academy of Medical Sciences (SYXK20220005). The anti-fatigue activity of the key active ingredients was evaluated using a zebrafish model. The results of the zebrafish activity evaluation showed that there were significant differences in the activities of the western ginseng samples from the two origins, and a total of 10 different saponins were identified as possibly related to the anti-fatigue activity after further metabolomic testing and pattern discrimination. The core anti-fatigue targets were screened with the help of component-disease target PPI, combined with pharmacophore-like parameters and molecular docking techniques, and pseudoginsenoside F11 was found to have good binding activity to five of the targets. Finally, the zebrafish model revealed that pseudoginsenoside F11 exhibited significant anti-fatigue activity. This study used metabolomics and zebrafish model to screen the key active substances of pseudoginsenoside F11 for its anti-fatigue activity, which will provide a reference for further research on the anti-fatigue of pseudoginsenosides.

Anti-osteoporosis mechanism of Panax quiquefolium L. based on zebrafish model and metabonomics / 药学学报

In this study, we investigated the anti-osteoporotic activity and mechanism of action of extract of Panax quiquefolium L. based on zebrafish model combined with metabolomics technology. A zebrafish model of prednisolone-induced osteoporosis was used to compare the anti-osteoporotic activity of Panax quiquefolium L., and the expression of osteoblast-associated genes and osteoclast-associated genes in zebrafish was detected by quantitative real-time PCR (qRT-PCR), using bone fluorescence area and fluorescence density as evaluation indexes. Metabolomics based on ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS) was used to explore the change patterns of biomarkers and the metabolic pathways affected. The results showed that the 50% ethanol extracts of Panax quiquefolium L. from Jilin, Canada, Wenden and the United States can significantly improve the bone fluorescence area of zebrafish compared with model group. Furthermore, four sources 50% ethanol extracts of Panax quiquefolium L. except United States also can significantly improve the bone fluorescence density of zebrafish. In addition, PCR showed that extract of Panax quiquefolium L. can significantly up-regulated the expression of vitamin D receptor b (vdrb), collagen type I α2 (col1a2) and cysteine-rich acidic secreted protein (sparc) genes, and down-regulated the expression of matrix metalloproteinase 9 (mmp9), anti-tartrase acid phosphatase (trap) and cathepsin K (ctsk) genes. Metabolomic analysis identified 24 key differential metabolites. Furthermore, pathway analysis showed that Panax quiquefolium L. could regulate the levels of 10 key biomarkers by participating in purine metabolism, tricarboxylic acid cycle and pentose phosphate metabolism and improve the osteoporosis status of zebrafish. This study preliminically revealed the anti-osteoporosis mechanism of 50% ethanol extract from Panax quiquefolium L. through multi-component, multi-target and multi-pathway and also provides theoretical basis for clinical development and utilization of anti-osteoporosis products of Panax quiquefolium L. This experiment was approved by the Experimental Animal Welfare Ethics Committee of the Institute of Biology, Shandong Academy of Sciences (approval number: SWS20181002).

Effects of lead and manganese combined exposure on neurodevelopmental toxicity and JNK expression in zebrafish / 环境与职业医学

Background Lead and manganese are heavy metal pollutants widely existing in the environment, which can accumulate in the human body through the food chain, exert neurotoxicity, and cause neurodegenerative disorders. Especially in early childhood, the developing blood-brain barrier and nervous system are highly susceptible to environmental chemical pollutants. Most of the previous studies focused on the toxic effects of single heavy metal such as lead or manganese, while the studies on combined toxic effect are still scarce, and involved mechanisms are still unclear. c-Jun N-terminal kinase (JNK) is involved in neuronal development and regeneration, and some studies have found that JNK is involved in lead or manganese induced neurotoxicity. Its role in the toxicity of combined lead and manganese is unknown. Objective To understand the neurodevelopmental toxicity mechanism and to observe changes of JNK expression in zebrafish induced by combined lead and manganese exposure at environmentlly low concentrations. Methods Zebrafish embryos within 2 h post fertilization (hpf) were divided into four groups: control group, lead exposure group (0.1 mg·L−1 lead acetate), manganese exposure group (0.3 mg·L−1 manganous chloride), and lead-manganese combined exposure group (0.1 mg·L−1 lead acetate +0.3 mg·L−1 manganous chloride) and exposed to lead or/and manganese at designed levels for 7 d. Spontaneous movements and motor locomotion were observed, and mortality rate were calculated. The changes of JNK mRNA expression in zebrafish were evaluated. Results The experimental results showed that no significant effect of lead or/and manganese on spontaneous movements and mortality rate was found in zebrafish compared with the control group (P＞0.05). The results of locomotion analysis showed that compared with the control group, the activity counts and activity distance of zebrafish in the manganese exposure group were slightly increased (P＜0.01); the activity counts and activity distance of zebrafish in the lead exposure group were reduced by 50% and those in the lead-manganese exposure group were reduced by 80% (P＜0.01). Compared with the lead exposure group, the activity counts and activity distance of zebrafish in the lead-manganese combined exposure group decreased significantly by 60% (P＜0.05). The real-time quantitative PCR results showed that the JNK mRNA expression level was significantly increased in the lead-manganese combined exposure group compared with the control group(P＜0.01). Conclusion Lead exposure combined with manganese exposure at environmentlly low concentration can induce neurodevelopmental toxicity to zebrafish. JNK may be involved in neurodevelopmental toxicity induced by the combined exposure to lead and manganese.

Improvement situation on indexes of the zebrafish disease model of non-alcoholic fatty liver disease with FGF21 analogues / 中华肝脏病杂志

Objective: To detect the therapeutic efficacy of FGF21 analogues on the zebrafish model of non-alcoholic fatty liver disease. Methods: A zebrafish model of non-alcoholic fatty liver disease was established by providing the normal diet fed to wild-type zebrafish three times daily. PF-05231023 was administered exogenously at a final concentration of 0.5 μmol/L. Body length, body weight, triglycerides, and other indexes were measured after 20 days. Pathological changes were evaluated in liver tissue sections by HE staining. Quantitative PCR was used to identify expressional changes in genes related to lipid metabolism, endoplasmic reticulum stress, and inflammation. Results: QPCR and immunofluorescence staining results showed that FGF21 was highly expressed in the zebrafish model group. The addition of the FGF21 analogue PF-05231023 significantly reduced the body length and body weight (P < 0.01), and the triglyceride content (P < 0.05) in the zebrafish model group. The liver HE staining results showed that PF-05231023 had alleviated the large and tiny bullae fat, lesions, and others in the zebrafish model group. The quantitative PCR results demonstrated that PF-05231023 reduced the expression of lipogenic factors (P < 0.01), inflammatory-related factors (P < 0.001), and genes related to endoplasmic reticulum stress (P < 0.05), but raised lipid-oxidation-related factors (P < 0.05) in the zebrafish model group. The addition of PF-05231023 reduced oleic acid-induced lipid and triglyceride levels in HepG2 cells. Conclusion: FGF21 analogue addition can improve indexes in the zebrafish disease model of non-alcoholic fatty liver disease.

Effects of lead exposure on development of heart and spine in zebrafish embryos / 环境与职业医学

Background Lead is widely distributed. Lead exposure interferes with early life development in zebrafish, but the mechanisms by which lead exposure affects skeletal development and cardiac development are not clear as yet. Objective To investigate the molecular mechanisms of bone development and cardiac development toxicity induced by lead acetate exposure. Methods Zebrafish embryos were exposed to different concentrations of lead acetate (0, 6, 12, 24, and 48 μmol·L−1) for 3 h post-fertilization (3 hpf) until 5 d post-fertilization (5 dpf). The malformation phenotypes of 5 dpf were counted, and the mRNA expressions of spinal development-related genes (bmp2b, bmp4, bmp9, runx2a, runx2b) and heart development-related genes (nkx2.5, myh6, myh7) were detected by quantitative PCR (qPCR). Expressions of genes of development-related regulatory pathways including Wnt/β-catenin pathway (wnt5a, wnt8a, wnt10a, β-catenin) and TGF-β pathway (tgf-β1, tgf-β2) as well as key molecule eph of Eph-Ephrin signaling were analyzed. Results At 5 dpf, the zebrafish in the lead acetate treated groups showed deformed phenotypes including spinal curvature and pericardial sac edema compared to the control group. In the lead acetate groups at 24 and 48 μmol·L−1, the spinal curvature deformity rates reached 26.47% and 71.52% (P<0.01) respectively. The qPCR results revealed that the expression levels of spinal development-related genes bmp2b, bmp4, bmp9, runx2a, and runx2b were downregulated in the 48 μmol·L−1 exposure group compared to the control group by 82.8%, 58.0%, 88.7%, 85.5%, and 69.2%, respectively (P<0.05 or P<0.01); the expression levels of heart development-related genes myh6, myh7, and nkx2.5 were down-regulated by 63.7%, 58.9%, and 55.2%, respectively (P<0.01); the expression levels of wnt8a and β-catenin in the Wnt/β-catenin pathway were down-regulated by 71.5% and 47.3% (P < 0.05 or P < 0.01), respectively; the expression level of tgf- β1 in the TGF-β pathway was down-regulated by 67.5% (P<0.01); the expression level of eph was down-regulated by 86.9% (P<0.01). Conclusion Lead acetate exerts developmental toxic effects on zebrafish heart and bone by down-regulating the expressions of genes related to spinal development and heart development, as well as inhibiting development-related Wnt/β-catenin and TGF-β pathways and Eph-Ephrin signaling, causing malformed phenotypes such as spinal curvature and pericardial sac edema.

Screening of active components and preliminary mechanism exploration of Lycii Fructus for improving osteoporosis based on the zebrafish model / 药学学报

Juvenile zebrafish were used to screen the active components of Lycii Fructus for improving osteoporosis. The screening results were further verified by zebrafish adult osteoporosis model and the action mechanism was explored. Prednisolone was used as the inducer to build osteoporosis models of juvenile and adult zebrafish, and 9 groups of samples of different extracts and chemical parts of Lycii Fructus were given. Alizarin red staining was applied for observing the scale matrix mineralization and bone resorption. The activities of osteoblasts and osteoclasts were detected using alkaline phosphatase (ALP) and tartrate resistant acid phosphatase (TRAP/TRACP) staining. The expressions of bone metabolism-related genes alp, osteoprotectin (opn), osteoblast specific transcription factor (sp7), cathepsin K (ctsk), tracp, and Runt family transcription factor 2b (runx2b) in each group were determined using quantitative polymerase chain reaction. The results showed that all components of Lycii Fructus improved the formation area of the first vertebrae, the staining light density value, and the number of vertebrae joints in juvenile zebrafish and the Lycium barbarum polysaccharide (LBP) treatment group exerted the best effect. In addition, LBP prevented the formation of bone resorption lacunae in zebrafish scales, increased ALP activity, decreased TRAP activity, up-regulated the alp, sp7, and opn genes, and lowered the expressions of ctsk and tracp genes. In conclusion, LBP regulated the activity of osteoblasts and osteoclasts, reduced bone resorption, promoted bone formation and enhanced bone density, which might be the main anti-osteoporosis active fraction of Lycii Fructus. This study provided modern scientific evidence for the scientific connotation of the traditional effect of "strengthening bones and muscles" of Lycii Fructus, provided the reference for the evaluation of the anti-osteoporosis activity of traditional Chinese medicine based on zebrafish adult model, and provided beneficial enlightenment for the bone health needs of the aging society population.

Hepatotoxicity and mechanism of Rhododendri Mollis Flos based on zebrafish model / 中国中药杂志

This study used the zebrafish model to explore the hepatotoxicity of Rhododendri Mollis Flos(RMF). The mortality was calculated according to the number of the survival of zebrafish larvae 4 days after fertilization under different concentration of RMF, and the dose-toxicity curve was fitted to preliminarily evaluate the toxicity of RMF. The liver phenotypes under the sublethal concentration of RMF in the treatment group and the blank control group were observed by hematoxylin-eosin(HE) staining and acridine orange(AO) staining. Meanwhile, the activities of alanine aminotransferase(ALT) and aspartate aminotransferase(AST) were determined to confirm the hepatotoxicity of RMF. Real-time quantitative polymerase chain reaction(real-time PCR) and Western blot were used to determine the expressions of genes and proteins in zebrafish larvae. Gas chromatography time-of-flight mass spectrometry(GC-TOF-MS) was used to conduct untargeted metabolomics testing to explore the mechanism. The results showed that the toxicity of RMF to zebrafish larvae was dose-dependent, with 1 100 μg·mL~(-1) of the absolute lethal concentration and 448 μg·mL~(-1) of sublethal concentration. The hepatocyte apoptosis and degeneration appeared in the zebrafish larvae under the sublethal concentration of RMF. The content of ALT and AST in zebrafish larvae at the end of the experiment was significantly increased in a dose-dependent manner. Under the sublethal concentration, the expressions of genes and proteins related to apoptosis in zebrafish larvae were significantly increased as compared with the blank control group. The results of untargeted metabolomics showed that the important metabolites related to the he-patotoxicity of RMF were mainly enriched in alanine, aspartic acid, glutamic acid, and other pathways. In conclusion, it is inferred that RMF has certain hepatotoxicity to zebrafish larvae, and its mechanism may be related to apoptosis.

Single-cell analysis reveals an Angpt4-initiated EPDC-EC-CM cellular coordination cascade during heart regeneration

Mammals exhibit limited heart regeneration ability, which can lead to heart failure after myocardial infarction. In contrast, zebrafish exhibit remarkable cardiac regeneration capacity. Several cell types and signaling pathways have been reported to participate in this process. However, a comprehensive analysis of how different cells and signals interact and coordinate to regulate cardiac regeneration is unavailable. We collected major cardiac cell types from zebrafish and performed high-precision single-cell transcriptome analyses during both development and post-injury regeneration. We revealed the cellular heterogeneity as well as the molecular progress of cardiomyocytes during these processes, and identified a subtype of atrial cardiomyocyte exhibiting a stem-like state which may transdifferentiate into ventricular cardiomyocytes during regeneration. Furthermore, we identified a regeneration-induced cell (RIC) population in the epicardium-derived cells (EPDC), and demonstrated Angiopoietin 4 (Angpt4) as a specific regulator of heart regeneration. angpt4 expression is specifically and transiently activated in RIC, which initiates a signaling cascade from EPDC to endocardium through the Tie2-MAPK pathway, and further induces activation of cathepsin K in cardiomyocytes through RA signaling. Loss of angpt4 leads to defects in scar tissue resolution and cardiomyocyte proliferation, while overexpression of angpt4 accelerates regeneration. Furthermore, we found that ANGPT4 could enhance proliferation of neonatal rat cardiomyocytes, and promote cardiac repair in mice after myocardial infarction, indicating that the function of Angpt4 is conserved in mammals. Our study provides a mechanistic understanding of heart regeneration at single-cell precision, identifies Angpt4 as a key regulator of cardiomyocyte proliferation and regeneration, and offers a novel therapeutic target for improved recovery after human heart injuries.

Acute Developmental Toxicity of Panax notoginseng in Zebrafish Larvae / 中国结合医学杂志

OBJECTIVE@#To evaluate toxicity of raw extract of Panax notoginseng (rPN) and decocted extract of PN (dPN) by a toxicological assay using zebrafish larvae, and explore the mechanism by RNA sequencing assay.@*METHODS@#Zebrafish larvae was used to evaluate acute toxicity of PN in two forms: rPN and dPN. Three doses (0.5, 1.5, and 5.0 µ g/mL) of dPN were used to treat zebrafishes for evaluating the developmental toxicity. Behavior abnormalities, body weight, body length and number of vertebral roots were used as specific phenotypic endpoints. RNA sequencing (RNA-seq) assay was applied to clarify the mechanism of acute toxicity, followed by real time PCR (qPCR) for verification. High performance liquid chromatography analysis was performed to determine the chemoprofile of this herb.@*RESULTS@#The acute toxicity result showed that rPN exerted higher acute toxicity than dPN in inducing death of larval zebrafishes (P<0.01). After daily oral intake for 21 days, dPN at doses of 0.5, 1.5 and 5.0 µ g/mL decreased the body weight, body length, and vertebral number of larval zebrafishes, indicating developmental toxicity of dPN. No other adverse outcome was observed during the experimental period. RNA-seq data revealed 38 genes differentially expressed in dPN-treated zebrafishes, of which carboxypeptidase A1 (cpa1) and opioid growth factor receptor-like 2 (ogfrl2) were identified as functional genes in regulating body development of zebrafishes. qPCR data showed that dPN significantly down-regulated the mRNA expressions of cpa1 and ogfrl2 (both P<0.01), verifying cpa1 and ogfrl2 as target genes for dPN.@*CONCLUSION@#This report uncovers the developmental toxicity of dPN, suggesting potential risk of its clinical application in children.

Immune regulation mechanism of Saposhnikoviae Radix polysaccharide based on zebrafish model / 中国中药杂志

The immunomodulatory effect of Saposhnikoviae Radix polysaccharide(SRP) was evaluated based on the zebrafish mo-del, and its mechanism was explored by transcriptome sequencing and real-time fluorescence-based quantitative PCR(RT-qPCR). The immune-compromised model was induced by navelbine in the immunofluorescence-labeled transgenic zebrafish Tg(lyz: DsRed), and the effect of SRP on the density and distribution of macrophages in zebrafish was evaluated. The effect of SRP on the numbers of macrophages and neutrophils in wild-type AB zebrafish was detected by neutral red and Sudan black B staining. The content of NO in zebrafish was detected by DAF-FM DA fluorescence probe. The content of IL-1β and IL-6 in zebrafish was detected by ELISA. The differentially expressed genes(DEGs) of zebrafish in the blank control group, the model group, and the SRP treatment group were analyzed by transcriptome sequencing. The immune regulation mechanism was analyzed by Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment, and the expression levels of key genes were verified by RT-qPCR. The results showed that SRP could significantly increase the density of immune cells in zebrafish, increase the number of macrophages and neutrophils, and reduce the content of NO, IL-1β, and IL-6 in immune-compromised zebrafish. The results of transcriptome sequencing analysis showed that SRP could affect the expression level of immune-related genes on Toll-like receptor pathway and herpes simplex infection pathway to affect the release of downstream cytokines and interferon, thereby completing the activation process of T cells and playing a role in regulating the immune activity of the body.

Efficacy of the herbal pair, Radix Achyranthis Bidentatae and Eucommiae Cortex, in preventing glucocorticoid-induced osteoporosis in the zebrafish model / 中西医结合学报

OBJECTIVE@#In traditional Chinese medicine, the herbal pair, Radix Achyranthis Bidentatae (RAB) and Eucommiae Cortex (EC), is widely used to treat osteoporosis. Herein, we determined whether this herbal pair can be used to ameliorate glucocorticoid (GC)-induced osteoporosis (GIOP) and find its optimal dosage in zebrafish.@*METHODS@#The characteristics of the aqueous extract of RAB and EC were separately characterized using high-performance liquid chromatography. Osteoporosis was induced in 5-day post-fertilization zebrafish larvae by exposing them to 10 μmol/L dexamethasone (Dex) for 96 h. Seven combinations of different ratios of RAB and EC were co-administered. Treatment efficacy was determined by calculating zebrafish vertebral area and sum brightness, via alizarin red staining, and by detecting alkaline phosphatase (ALP) activity. Multiple regression analysis was conducted to test the optimal dosage ratio.@*RESULTS@#According to the Chinese Pharmacopoeia (2015), β-ecdysone (β-Ecd) is a major bioactive marker in RAB extract, while pinoresinol diglucoside (PDG) is the major marker in EC extract. Both of β-Ecd and PDG content values aligned with the Chinese Pharmacopoeia standards. Treatment with 10 μmol/L Dex reduced zebrafish vertebral area, sum brightness, and ALP activity, but RAB and EC attenuated these effects. Combining 50 µg/mL RAB and 50 µg/mL EC was optimal for preventing GIOP in zebrafish. Reverse transcription-quantitative polymerase chain reaction was used to evaluate the mRNA expression of osteogenesis-related genes. A treatment of 10 μmol/L Dex decreased runt-related transcription factor 2 (Runx2), osteogenic protein-1 (OP-1), bone γ-carboxyglutamic acid-containing protein (BGLAP), and β-catenin levels. This effect was counteracted by RAB and EC co-treatment (P < 0.05). Additionally, the effect of using the two herbal extracts together was better than single-herb treatments separately. These results demonstrated that RAB and EC preserve osteoblast function in the presence of GC. The best mass ratio was 1:1.@*CONCLUSION@#RAB and EC herbal pair could ameliorate GC-induced effects in zebrafish, with 1:1 as the optimal dosage ratio.

Single-copy Loss of Rho Guanine Nucleotide Exchange Factor 10 ( arhgef10) Causes Locomotor Abnormalities in Zebrafish Larvae / 生物医学与环境科学（英文）

OBJECTIVE@#To determine if ARHGEF10 has a haploinsufficient effect and provide evidence to evaluate the severity, if any, during prenatal consultation.@*METHODS@#Zebrafish was used as a model for generating mutant. The pattern of arhgef10 expression in the early stages of zebrafish development was observed using whole-mount in situ hybridization (WISH). CRISPR/Cas9 was applied to generate a zebrafish model with a single-copy or homozygous arhgef10 deletion. Activity and light/dark tests were performed in arhgef10 -/-, arhgef10 +/-, and wild-type zebrafish larvae. ARHGEF10 was knocked down using small interferon RNA (siRNA) in the SH-SY5Y cell line, and cell proliferation and apoptosis were determined using the CCK-8 assay and Annexin V/PI staining, respectively.@*RESULTS@#WISH showed that during zebrafish embryonic development arhgef10 was expressed in the midbrain and hindbrain at 36-72 h post-fertilization (hpf) and in the hemopoietic system at 36-48 hpf. The zebrafish larvae with single-copy and homozygous arhgef10 deletions had lower exercise capacity and poorer responses to environmental changes compared to wild-type zebrafish larvae. Moreover, arhgef10 -/- zebrafish had more severe symptoms than arhgef10 +/- zebrafish. Knockdown of ARHGEF10 in human neuroblastoma cells led to decreased cell proliferation and increased cell apoptosis.@*CONCLUSION@#Based on our findings, ARHGEF10 appeared to have a haploinsufficiency effect.