Spermary promotes sexual behavior,gonadal development and sperm count production in male zebrafish / 重庆医学

Objective To explore the effects of spermary on sexual behavior,gonadal development and sperm count production.Methods Fifty-six male zebrafishes of 10-month-old AB strain after fertilization were randomly divided into 7 tanks and set up as the normal group,model group,positive control group(clomiphene citrate group,Wuzi Yanzong Pills group),and Spermary low,medium and high concentration groups,8 fishes in each group.Except for the normal group,cyclophosphamide was given in water solution to establish the zebrafish oligospermia model,respectively.On 9 d of modeling,the positive control group was ad-ministered at a concentration of 0.1 μg/mL in the clomiphene citrate group and 6 μg/mL in the Wuzi Yanzong Pill group;the spermary low,medium and high concentration groups were administered at 200,300,900 μg/mL,respectively.On 16 d of modeling,the normal female zebrafishes were placed in the culture tank of each group in a 1∶1 ratio,and the frequency of tail-chasing was observed and recorded in male and female fishes.The body length,weight,testis weight and sperm count were measured and the statistical analysis was performed by comparing the differences among the groups before and after drug administration(one-way ANOVA).Results Com-pared with the normal group,the frequency of tail-chasing of zebrafishes,body length,body weight,testis weight and sperm count in the model group were significantly decreased(P＜0.05).Compared with the model group,the frequency of tail-chasing of zebrafishes,body length,body weight,testis weight and sperm count in the spermary low,medium and high concentration groups all were significantly increased(P＜0.05),in which the vitality change of sexual behavior in the spermary medium concentration group was most obvious,and the increase of sperms count was most obvious.Conclusion A certain dose of spermary could effectively promote the sexual behavior,gonadal development and sperm count production in male zebrafish with oligospermia.The efficacy of spermary in enhancing the male sexual function and treating oligozoospermia and infertility de-serves to be studied.

Study on anti-osteoporosis effect of different extracts of Polygoni Multiflori Radix Praeparata on zebrafish / 国际中医中药杂志

Objective:To study on anti-osteoporosis effect of different extracts of Polygoni Multiflori Radix Praeparata on zebrafish.Methods:Three kinds extracts of Polygoni Multiflori Radix Praeparata, anthraquinone and stilbene glycosides and the removal of anthraquinone and stilbene glycosides were prepared. Prednisolone was used to construct the osteoporosis model of young zebrafish. Normal control group, model group, disodium etidronate group and low-, medium- and high-dosage groups of different extracts of Polygoni Multiflori Radix Praeparata were set up. Alizarin red staining was used to investigate the mineralized skull area and bone density of juvenile zebrafish in each group. Alkaline phosphatase (AKP) and tartrate-resistant acid phosphatase (TRACP) kits were used to detect the activity of osteoblast and osteoclast enzymes in zebra larvae. The qRT PCR method was used to detect the mRNA expressions of osteoporosis related genes Runx2b, col1a2, sparc, and vdrb in each group of zebrafish.Results:Compared with model group, the skull mineralized area and bone mineral density in different extracts of Polygoni Multiflori Radix Praeparata significantly increased ( P<0.01). Polygoni Multiflori Radix Praeparata, anthraquinone and stilbene glycosides and the removal of anthraquinone and stilbene glycosides (medium- and high-dosage) could significantly increase the AKP activity of zebrafish ( P<0.01), and lower the TRAP activity of zebrafish ( P<0.01); the mRNA expression levels of Runx2b, col1a2, sparc and vdrb in juvenile zebrafish osteoporosis model were significantly up-regulated by different extracts of Polygoni Multiflori Radix Praeparata. ( P<0.01). Conclusion:Polygoni Multiflori Radix Praeparata, Anthraquinone and stilbene glycosides and the removal of anthraquinone and stilbene glycosides show better anti-osteoporosis effects. The comparison of the efficacy of three extracts from Polygonum multiflorum shows that in addition to anthraquinone and stilbene glycosides, other chemical components of Polygonum multiflorum have anti-osteoporosis effects.

Application progress of zebrafish(Danio rerio)model in circadian rhythm research / 军事医学

Circadian rhythm is one of the biorhythms formed by organisms in the process of evolution to adapt to the rotation of the earth,which is manifested as a cyclical biorhythm of about 24 hours produced by the body under the control of the internal biological clock,coordinating sleep/wakefulness,body temperature regulation,endocrine time and other activities.Long-term circadian rhythm disorders can cause increased risk of metabolic disorders,gastrointestinal diseases,neurodegenerative diseasesand other illnesses.As a typical model animal,the aquatic organism zebrafish(Danio rerio)has been widely used in experimental studies of circadian rhythm.This paper introduces in detailthe operating mechanism of zebrafish circadian clock,the influencing factors of the input system,the genes and pathways of the circadian clock,and the physiological output,summarizes the application and advantages in circadian rhythm research,finally looks forward to future research and development,in order to provide theoretical support for circadian rhythm regulation mechanism research,related drug development and disease treatment strategies.

Ethyl acetate fraction of Sargassum pallidum extract attenuates particulate matterinduced oxidative stress and inflammation in keratinocytes and zebrafish

@#Objective: To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter (PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish. Methods: HaCaT cells and zebrafish were used to evaluate the protective effects of the ethyl acetate fraction of Sargassum pallidum extract against PM-induced oxidative stress and inflammation. The production of nitric oxide (NO), intracellular ROS, prostaglandin E2 (PGE2), and pro-inflammatory cytokines, and the expression levels of COX-2, iNOS, and NF-κB were evaluated in PM-induced HaCaT cells. Furthermore, the levels of ROS, NO, and lipid peroxidation were assessed in the PM-exposed zebrafish model. Results: The ethyl acetate fraction of Sargassum pallidum extract significantly decreased the production of NO, intracellular ROS, and PGE2 in PM-induced HaCaT cells. In addition, the fraction markedly suppressed the levels of pro-inflammatory cytokines and inhibited the expression levels of COX-2, iNOS, and NF-κB. Furthermore, it displayed remarkable protective effects against PM-induced inflammatory response and oxidative stress, represented by the reduction of NO, ROS, and lipid peroxidation in zebrafish. Conclusions: The ethyl acetate fraction of Sargassum pallidum extract exhibits a protective effect against PM-induced oxidative stress and inflammation both in vitro and in vivo and has the potential as a candidate for the development of pharmaceutical and cosmeceutical products.

Retinal microstructure and developmental characteristics in Zebrafish / 解剖学报

Objective To study the microscopic structure and morphological characteristics of Zebrafish eyeball and retina at different developmental stages, and to lay a foundation for visual research model. Methods Select eight groups of zebrafish at different ages, with six fish in each group, 48 fish in total. Optical microscopy and transmission electron microscopy were used to observe the eyeball structure of Zebrafish at different developmental stages, and the thickness of retinal each layer was measured to analyze the temporal and spatial development pattern. The morphological characteristics of various cells in the retina and the way of nerve connection were observed from the microscopic and ultrastructural aspects, especially the structural differences between rod cells and cone cells. Results The retina of Zebrafish can be divided into ten layers including retinal pigment epithelial layer, rod cells and cone cells layer, outer limiting membrane, outer nuclear layer, outer plexiform layer, inner nuclear layer, inner plexiform layer, ganglion cell layer, nerve fiber layer, inner limiting membrane. Rod cells had a smaller nucleus and a higher electron density than cone cells. Photoreceptor terminals were neatly arranged in the outer plexiform layer, forming neural connections with horizontal cells and bipolar cells, and several synaptic ribbons are clearly visible within them. In Zebrafish retina, ganglion cell layer and inner plexiform layer are the earliest developed. With the growth and development of Zebrafish, the thickness of rod cells and cone cells layer and retinal pigment epithelial layer gradually increases, and the retinal structure was basically developed in about 10 weeks. Conclusion The retinal structure of Zebrafish is typical, with obvious stratification and highly differentiated nerve cells. There are abundant neural connections in the outer plexiform layer. The ocular development characteristics of Zebrafish are similar to those of most mammals.

Neurodevelopmental toxicity and Parkinsonism-like symptoms induced by nano-alumina exposure in zebrafish / 环境与职业医学

Background Nano-alumina (nano-Al2O3) is a widely utilized nanomaterial. Its impacts on the environment and biological systems have garnered significant attention. Zebrafish serves as a common model organism in scientific research due to its high homology with the human genome and is extensively used in toxicity studies. Objective To investigate the developmental toxicity and neurotoxicity of nano-Al2O3 exposure in zebrafish and the corresponding mechanisms of action. Method Zebrafish embryos at 6 h post-fertilization (hpf) were randomly assigned to a control group and five dose groups exposed to nano-Al2O3 at concentrations of 200, 400, 600, 800, and 1000 μg·mL−1, respectively. Thirty embryos were included in each group, and the culture medium was replaced every 24 h until 144 hpf. The hatching rates at 48 and 72 hpf and the cumulative malformation rates up to 144 hpf were calculated. At 144 hpf, a zebrafish behavior analyzer was used to record the movement trajectories of the zebrafish, and the total distance traveled and average speed were analyzed for each group. At 144 hpf, the development of dopaminergic neurons in transgenic zebrafish expressing vmat2: GFP, brain vessels in those expressing vegf: GFP, and central nervous system neurons in those expressing elavl3: EGFP were observed under a fluorescence microscope, and statistical analysis was conducted using Image Pro Plus. Real-time quantitative PCR was employed to detect the expression levels of neuron development-related genes (syn2α, gap43, dat), Lewy body formation-related gene (α-syn), and autophagy-related genes (pink1, parkin) at 144 hpf. Results Compared to the control group, the nano-Al2O3 exposed groups exhibited reduced hatching rates at 48 hpf and increased cumulative malformation rates (P<0.05), with phenomena such as delayed development, absence of the swim bladder, and body curvature. The autonomous behavioral tests revealed that the nano-Al2O3 exposed zebrafish showed a decrease in the total distance swum (P<0.001) and a significant reduction in average speed compared to the control group. The fluorescence observations indicated that the length of dopaminergic neurons in vmat2: GFP transgenic zebrafish was reduced in the nano-Al2O3 exposed groups (P<0.001). Additionally, vegf: GFP transgenic zebrafish exhibited a significant absence of brain vessels, while elavl3: EGFP transgenic zebrafish showed a weakened fluorescence intensity of central nervous system neurons (P<0.001) and a decreased length of these neurons (P<0.01). The real-time quantitative PCR analysis revealed that compared to the control group, the gene expression levels of α-syn, syn2α, dat, and gap43 were upregulated in the zebrafish exposed to nano-Al2O3 (except for the 400 μg·mL−1 exposure group) (P<0.01), while the expression levels of parkin were downregulated in the 600 and 800 μg·mL−1 nano-Al2O3 exposed groups, and the expression levels of pink1 were downregulated in all exposure groups except for the 200 μg·mL−1 group (P<0.05). Conclusion Exposure to nano-Al2O3 exhibits developmental toxicity in zebrafish larvae and induces Parkinsonism-like symptoms in zebrafish. The preliminary speculation of the mechanism suggests that it may be related to nano-Al2O3-induced mitochondrial autophagy impairment.

Effects and mechanism of ultra-high dose rate irradiation in reducing radiation damage to zebrafish embryos / 中华放射医学与防护杂志

Objective:To conduct a comparative analysis of the radiation damage to zebrafish embryos and the associated biological mechanism after ultra-high dose rate (FLASH) and conventional dose rate irradiation.Methods:Zebrafish embryos at 4 h post-fertilization were exposed to conventional and FLASH irradiation (9 MeV electron beam). The mortality and hatchability of zebrafish after radiation exposure were recorded. Larvae at 96 h post-irradiation underwent morphological scoring, testing of reactive oxygen species (ROS) levels, and analysis of changes in oxidative stress indicators.Results:Electron beam irradiation at doses of 2-12 Gy exerted subtle effects on the mortality and hatchability of zebrafish embryos. However, single high-dose irradiation (≥ 6 Gy) could lead to developmental malformation of larvae, with conventional irradiation showing the most significant effects ( t = 0.87-9.75, P < 0.05). In contrast, after FLASH irradiation (≥ 6 Gy), the ROS levels in zebrafish and its oxidative stress indicators including superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) were significantly reduced ( t = 0.42-15.19, P < 0.05). There was no statistically significant difference in ROS levels in incubating solutions after conventional and FLASH irradiation ( P > 0.05). Conclusions:Compared to conventional irradiation, FLASH irradiation can reduce radiation damage to zebrafish embryos, and this is in a dose-dependent manner. The two irradiation modes lead to different oxidative stress levels in zebrafish, which might be a significant factor in the reduction of radiation damage with FLASH irradiation.

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.

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).

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.

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.

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.

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.

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.

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.

Effects of Liuwei Anshen Capsule on Estrogen Level of Rhythm Gene and Ovarian Function in Sleep-Deprived Zebrafish Model / 世界科学技术-中医药现代化

Objective Observe the effect of Liuwei Anshen Capsule on sleep improvement of aged sleep deprivation zebrafish model.Methods Sixty 18-month-old female zebrafish were randomly divided into blank group,model group,Liuwei Anshen group,and melatonin group.The zebrafish in the blank group were raised under normal lighting conditions,and the other three groups were constructed with continuous lighting for 3 days.Zebrafish in Liuwei Anshen group were treated with Liuwei Anshen capsule water solution 0.000 50 mg·mL-1 for 3 days on the basis of model group,and zebrafish in melatonin group were treated with melatonin aqueous solution 0.2 mg·mL-1 on the basis of model group for 3 days.After 3 days,the zebrafish behavior system was used to detect the resting time of zebrafish in each group.qRT-PCR method was used to detect cyclin 1a(per1a),cyclin2(per2),circadian motor output cycle 1a(clock1a),cryptochrome 1b(cry1b),and 5-hydroxyindoleacetic acid(5-htiaa)in each group of zebrafish and follicle-stimulating hormone beta(fshβ)gene expression levels.Western blot was used to detect the expression levels of estrogen receptorα(Esrα),Fshβand luteinizing hormone(Lh)in zebrafish in each group.HE staining was used to observe the ovary of zebrafish in each group.Results Compared with the zebrafish in the blank group,the resting time of the zebrafish in the model group decreased significantly(P<0.01)during the 24 hours of observation.After the intervention of Liuwei Anshen Capsule and melatonin,the resting time of the zebrafish was significantly increased.(P<0.01).Compared with the zebrafish in the blank group,the mRNA expressions of zebrafish circadian clock genes per1a,per2,clock1a,cry1b,5-htiaa,and fshβ all showed a downward trend after sleep deprivation(P<0.05,P<0.01).After the intervention of Liuwei Anshen Capsules,the mRNA expressions of per1,clock1a,cry1b,5-htiaa and fshβ were all up-regulated(P<0.05,P<0.01).Compared with the zebrafish in the blank group,the protein expressions of Esrα and Lh in the zebrafish of the model group were up-regulated(P<0.05),the expression of Fshβ protein was down-regulated(P<0.05),after the intervention of Liuwei Anshen Capsules,the above proteins did not change significantly.The ovarian tissue cells of the zebrafish in the blank group had normal morphology and a large number of primary oocytes,while the ovarian tissue cells of the zebrafish in the model group were damaged in morphology and the number of primary oocytes decreased,after the intervention of Liuwei Anshen Capsule and melatonin,the cell morphology of zebrafish ovarian tissue was still damaged to varying degrees,but the whole was relatively intact,and the number of primary oocytes increased.Conclusion The insomnia of aged zebrafish may be caused by multiple factors.Liuwei Anshen capsule has significant effects on estrogen level of rhythm gene and ovarian function of sleep-deprived aged zebrafish.

Fine Structure of the Trunk Kidney and Distribution of Its Secreted Exosomes in the Adult Zebrafish / 实验动物与比较医学

ObjectiveTo observe the fine structure of the trunk kidney in zebrafish, and to identify its secreted exosomes. MethodsThe microstructure and ultrastructure of the trunk kidney in zebrafish were observed by light microscopy and electron microscopy, and the particle size of exosomes was detected by nanoparticle tracking analysis (NTA). ResultsThe trunk kidney was close and parallel to the spine in adult zebrafish. The nephron consisted of renal tubules and renal corpuscles. The renal tubules could be further divided into three types: proximal convoluted tubules, distal convoluted tubules, and cervical segments. The renal corpuscles were composed of glomerulus and renal capsules. The periodic acid-Schiff (PAS) staining results revealed that there were abundant glycogen granules in the proximal convoluted tubules, with brush-like outline in the apical surface of epithelial cells. Under transmission electron microscopy (TEM), there were exosomes distributed in the lumen of renal tubules, with numerous late endosomes and few number of multivesicular bodies (MVBs) in the cytoplasm of the epithelial cells concentrating on the apical side. Meanwhile, MVBs were also distributed in the apical regions of the renal tubules and the podocytes of the renal glomeruli. Immunohistochemical staining results showed that CD9, CD63 and TSG101 were strongly expressed in the lumen surface of the renal tubules, but weakly expressed in the corpuscles and lumen. NTA and TEM results showed that the exosomes isolated from zebrafish trunk kidney were saucer-like outline, and the particle size mode was 144.4 nm, which was consistent with the characteristics of morphological futures of exosome. ConclusionThe zebrafish somatic kidney has the typical structure of the mammalian kidney and is the urinary organ in the body. The renal tubules have the ability to secrete exosomes, and their formation is a process of releasing poly-vesicles to the free surface of epithelial cells into the extracellular space. This study laid a morphological foundation for further study of exosomes in urinary function in aquatic experimental animals as well as the development and application of related models.

Downregulation of Micall2a Gene Expression Inhibited Vascular Development in Zebrafish / 实验动物与比较医学

Objective To explore the expression pattern of Micall2a gene during the early development of zebrafish embryos and the effect of this gene on zebrafish vascular development.MethodsWhole embryo in situ hybridization was used to detect Micall2a expression levels at different stages of early embryo development of Tg (fli:GFP) transgenic (labeled with green fluorescent protein) and wild type zebrafish (AB). Micall2a gene expression was downregulated by microinjection of a morpholine antisense oligonucleotide, and real-time fluorescent quantitative PCR was used to detect mRNA expression of the gene at different developmental stages of zebrafish embryos. Laser confocal microscopy was used to observe and analyze vascular phenotypic changes in zebrafish after the downregulation of Micall2a. ResultsMicall2a was expressed in the brain, heart, and vascular system of zebrafish embryos at the 24th, 36th, and 48th hours post fertilization. The mRNA level of Micall2a increased after microinjection of morpholine antisense oligonucleotides, inhibiting vascular development in zebrafish embryos, resulting in internode angiogenesis defects in zebrafish. ConclusionDownregulation of Micall2a expression inhibits the development of blood vessels in zebrafish.

Advances and Applications in Animal Models of Neuroblastoma / 实验动物与比较医学

Neuroblastoma (NB) is one of the most common malignant solid tumors in children, ranks fourth in the incidence of pediatric tumors, and accounts for 15% of pediatric tumor deaths in children in China. Despite the development of new treatment options, the prognosis for high-risk patients is still poor. An animal model that can replicate the tumorigenesis of NB is an important tool for the prevention and treatment of NB. However, there are currently no animal models that can simulate all features of human NB. To provide a reference for the construction of animal models and treatment of NB, this article introduced several animal models of NB that have been extensively researched: the mouse, chick embryo chorioallantoic membrane, and zebrafish models. At the same time, it elaborated on the species, construction methods, characteristics, advantages and disadvantages, and research progress in NB.

An Optimized Experimental Zebrafish Breeding Scheme for Significantly Enhancing Reproductive Efficiency and Service Life / 实验动物与比较医学

ObjectiveTo solve the problems of delayed growth and development and insufficient spawning of experimental Zebrafish, so as to improve the reproductive efficiency and service life of experimental Zebrafish. MethodsThe zebrafish at the age of 2 months after fertilization were divided into two groups. The experimental group was fed with dry commercial diets specifically designed for ornamental fish or frozen adult brine shrimp, while control group was fed with live laval brine shrimp. Within a period of 70 days, the growth performance of the zebrafish was evaluated by measuring body length and weight, and the reproductive performance was assessed by measuring the fecundity and spawning rate. Zebrafish with apparent goiter disease were fed with dry commercial diets, and the inhibitory effect of the pellets on this disease was evaluated by measuring the diameter of the thyroid enlargement lesion. The three feeding methods were combined, and the feeding plan was optimized. The actual effects of the plan on zebrafish rearing were validated through reproductive performance tests. ResultsStarting from 60 days post-fertilization (dpf) until 111 dpf, the body length and weight of the dry commercial diets feed group gradually surpassed those of control group (all P<0.000 1). From 60 dpf to 96 dpf, the growth trend in body length of the adult brine shrimp group was similar to that of control group, but the female fish in the adult brine shrimp group had significantly higher body weight than the female fish in control group at 75-82 dpf (P<0.000 1). Compared to control group, there was a significant difference in body color between males and females in the adult brine shrimp group, and at 75 dpf, gender could be accurately distinguished by body color differences. Furthermore, the spawning rate of the zebrafish in the adult brine shrimp group at 3 months of age was significantly higher than that of control group (94.44% vs. 27.78%, P<0.05). Additionally, after feeding with the dry commercial diets for 130 days, all thyroid enlargement lesions in the experimental zebrafish disappeared. Based on the above results, the three feeding methods were combined and the feeding plan for zebrafish older than 2 months of age was optimized as follows: feed live brine shrimp in the morning, and alternate between dry commercial diets and adult brine shrimp in the afternoon. This feeding plan lasts until the age of 12 months. The spawning rate of Zebrafish can maintan 70%, and the spawning amount can reach (233.6±3.95) eggs. The fertilization rate and hatching rate were 97.47% and 90.24%, respectively, both significantly higher than those of control group (P<0.001, or P=0.01). ConclusionCompared to live brine shrimp feed, the dry commercial diets feed significantly improves the growth performance of zebrafish and has a therapeutic effect on thyroid enlargement disease. On the other hand, adult brine shrimp feed significantly enhances the early reproductive performance of zebrafish. The optimized feeding plan successfully improves the spawning efficiency of laboratory zebrafish, prolonging their reproductive lifespan and better supporting relevant scientific research.