Mechanism of ellagic acid improving cognitive dysfunction in APP/PS double transgenic mice based on PI3K/AKT/GSK-3β signaling pathway / 中国药理学通报

Aim To investigate the effect of ellagic acid (EA) on cognitive function in APP/PS 1 double- transgenic mice, and to explore the regulatory mechanism of ellagic acid on the level of oxidative stress in the hippocampus of double-transgenic mice based on the phosphatidylinositol 3-kinase/protein kinase B/glycogen synthase kinase-3 (PI3K/AKT/GSK-3 β) signaling pathway. Methods Thirty-two SPF-grade 6-month-old APP/PS 1 double transgenic mice were randomly divided into four groups, namely, APP/PS 1 group, APP/PS1 + EA group, APP/PS1 + LY294002 group, APP/PS 1 + EA + LY294002 group, with eight mice in each group, and eight SPF-grade C57BL/6J wild type mice ( Wild type) were selected as the blank control group. The APP/PS 1 + EA group was given 50 mg · kg

Huanglian Jiedutang Regulates HIF-1α/VEGF Signaling Pathway to Improve Learning and Memory Abilities of APP/PS1 Transgenic Mice / 中国实验方剂学杂志

ObjectiveTo reveal the effects of Huanglian Jiedutang （HLJDT） on the learning and memory abilities of APP/PS1 transgenic mice via hypoxia-inducible factor-1α （HIF-1α）/vascular endothelial growth factor （VEGF） signaling pathway. MethodForty 5-month-old β-amyloid precursor protein （APP）/presenilin 1（PS1） mice were randomized into the model， donepezil （0.001 g·kg-1·d-1）， and low-， medium-， and high-dose （1.5， 3， 6 g·kg-1·d-1， respectively） HLJDT groups， and 8 C57BL/6 mice were taken as the normal group. After 45 days of continuous administration， Morris water maze test was conducted， and the organ indexes were calculated. The morphological structure of cerebral vascular endothelial cells in mice was observed under a transmission electron microscope. Western blot was employed to measure the protein levels of APP， HIF-1α， VEGF，VEGFA， and brain-derived neurotrophic factor （BDNF） in the hippocampus. The mRNA levels of APP， HIF-1α， and VEGF were determined by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. ResultCompared with the normal group， the model group showed prolonged escape latency （P<0.05）， reduced distance and time around the target platform （P<0.05）， decrease brain and spleen indexes （P<0.05）， vascular endothelial cells with karyopyknosis and not abundant cytoplasm， up-regulated protein levels of APP， HIF-1α， VEGF， and VEGFA （P<0.05）， down-regulated protein level of BDNF （P<0.05）， and up-regulated mRNA levels of APP， HIF-1α， and VEGF （P<0.05） in the hippocampus. Compared with the model group， high-dose HLJDT shortened the escape latency （P<0.05）， increased the distance and time around the target platform （P<0.05）， raised the brain and spleen indexes （P<0.05）， repaired the organelles of vascular endothelial cells， down-regulated the protein levels of APP， HIF-1α， VEGF， and VEGFA （P<0.05）， up-regulated the protein level of BDNF （P<0.05）， and down-regulated the mRNA levels of APP， HIF-1α， and VEGF （P<0.05） in the hippocampus. ConclusionHLJDT can improve the learning and memory abilities of mice by reducing the expression of HIF-1α and VEGF， thus protecting the nerves.

Alterations of gut microbiota composition and cogni-tive behavior in APP/PS1/tau triple-transgenic mouse model of Alzheimer's disease / 中国药理学与毒理学杂志

OBJECTIVE Alzheimer's disease(AD)is a progressive neurological disease.Given the important role of gut microbiota composition in AD pathology,the observed perturbation in the microbiota composition and diversity may serve as the mechanisms underlying age-dependent APP/PS1/tau triple-transgenic mouse(3×Tg-AD)mice amyloid deposition and memory deficits.Here-in,we intended to investigate the gut microbiota and as-sessed its relationship with the triggering and develop-ment of cognitive impairment of AD.METHODS This study involves the comparative assessment of spatial learning,amyloid β-protein(Aβ)accumulation,and fecal microbiota alterations in 3×Tg-AD mice from three age groups:AD asymptomatic stage(3 m),presymptomatic stage(6 m),and the symptomatic stage of AD(9 m).RE-SULTS We demonstrate that spatial memory deficits,brain Aβ accumulation,and weight gain in 3×Tg-AD mice gradually appear after 6 months of age.However,the total gut bacterial counts underwent changes from 3 to 6 months of age and were further altered at 9 months of age.Importantly,changes in gut bacteria abundance of Desulfobacterota and Actinobacteriota phylain 6-month-old mice preceded apparent spatial memory deficits.CONCLUSION Changes in the gut microbial community are one of the mechanisms of early AD pathology.

Flavonoid compounds improve hippocampal neuro-genesis and cognitive dysfunction in mice / 中国药理学与毒理学杂志

OBJECTIVE To investigate the improve-ment functions of flavonoid compounds on temozolomide(TMZ)-,aging-or AD model-induced dysregulation of hip-pocampal NSC lineage progression,retardancy of den-dritic spine maturation in new-born neurons,as well as impairment of hippocampal-related learning and memory.METHODS We applied 30-week-old neural stem cell(NSC)specific promoter Nestin-GFP and NestinCreERT2:Rosa26-LSL-tdTomato transgenic mice and 16-week-old AD model 5XFAD transgenic mice,together with hippo-campal microinjection(ih),endogenous fluorescence trac-ing and immunofluorescent staining.RESULTS Both fla-vonoid compound A and its functional derivative flavo-noid compound B dose-dependently improved TMZ-,aging-or AD-induced defects of hippocampal NSC lin-eage progression and the maturation of dendritic spines of newborn neurons,thereby improving hippocampus related learning and memory.CONCLUSION This paper provides a new idea and treatment strategy for the devel-opment of new flavonoids that can promote neurogene-sis for neurodegenerative diseases and aging.

Effect of expressing of anti-PD-1 antibody in mouse mammary gland on spleen T cells in transgenic mice / 生物工程学报

This study aims to investigate the effect of anti-PD-1 antibody expressed in mouse mammary gland on the surface antigen protein of spleen T cells, cytokine expression, spleen CD4+ T cell proliferation and proliferation related pathways of transgenic mice at the cellular level. Transgenic mice expressing anti-human PD-1 antibody at 8 weeks of age without pregnancy and 18 weeks of age with lactation were divided into two groups, with transgenic negative mice in each group as the control. Spleen lymphocytes were extracted and the changes of spleen lymphocytes were detected. Compared with transgenic negative mice, the proportion of effector T cells of spleen T cells in the immune system of transgenic mice with anti-PD-1 antibody expressed in breast increased, the proportion of Treg cells decreased, and the IFN-γ, IL-17 and IL-2 expressed in CD4+ T cells increased in varying degrees. Moreover, IL-4, IL-10 and TGF-β in CD4+ T cells did not change, nor did some cell surface protein molecules related to T cell stimulate. There was no significant difference in T cell proliferation between transgenic positive and transgenic negative mice. In transgenic positive mice, the expression of phosphorylated proteins in PI3K/Akt/mTOR and RAS/MEK/ERK pathways were partially up-regulated, but the whole pathway was not completely up-regulated. Therefore, it is feasible to use transgenic mice as host to express monoclonal antibodies related to immune system such as anti-PD-1 antibody.

Construction of a novel time-specific NLRP3 transgenic mouse model by Cre-LoxP system / 中国药理学通报

Aim To construct and identify a new time-specific NLRP3 point mutation transgenic mouse model by Cre-LoxP system. Methods Cre-LoxP system was used to generate NL-RP3

Myocardial specific overexpression of Sirt1 inhibits recovery of cardiac function in mice with myocardial ischemia / 中国药理学通报

Aim To investigate the effect of overexpression of silent information regulator 1 (Sirtl) on cardiac function in mice with myocardial ischemia. Methods Myocardial specific Sirtl overexpression transgenic mice (Sirtl-Tg) and littermate control mice (C57BL/6J), half male and half female, were randomly divided into control sham operation group (Con), control model group (Con +ISO), Sirtl overexpression sham operation group (Sirtl-Tg) and Sirtl overexpression model group (Sirtl-Tg + ISO). Isoproterenol (ISO) was injected subcutaneously into the back of the neck at 100 mg • kg

Time dependent expression profiling of PTK2B and its relationship with Aβ, Tau and LRP-1 in hippocampus and blood of APPswe/PS1dE9 double-transgenic mouse / 中国应用生理学杂志

Objective: To uncover the time-dependent expression pattern of ptk2b gene and ptk2b-encoded protein, protein tyrosine kinase 2 beta(PTK2B), in the brain tissues of transgenic animal models of Alzheimer's disease (AD) and its relationship with the levels of Aβ1-42, phosphorylation of Tau (p-Tau) and low density lipoprotein receptor-related protein-1(LRP-1) in blood and brain tissues. Methods: In this study, 5-, 10- and 15-month-old APPswe/PS1dE9 double-transgenic mice harboring the genotype of AD confirmed by the gene test were divided into the 5-, 10- and 15-month-old experiment groups, and simultaneously, age-matched C57BL/6J mice were placed into the corresponding control groups, with 8 mice in each group. All mice were subjected to the Morris Water Maze for test of cognitive and behavioral ability. Expression profiles of PTK2B, Aβ1-42, p-Tau/Tau and LRP-1 in the hippocampus or blood of mice were quantified by using the immunohistochemistry staining, Western blot or enzyme-linked immunosorbent assay (ELISA), while the mRNA expression of ptk2b in the hippocampus was quantified by using the real-time quantitative polymerase chain reaction (qRT-PCR). Results: Results of experiment groups demonstrated that as mice aged, the expression levels of PTK2B, ptk2b mRNA, Aβ1-42 and p-Tau/Tau in the hippocampus were increased, and the expression of LRP-1 was decreased gradually. While in the blood, the level of Aβ1-42 was decreased, and the cognitive and behavioral ability was decreased in an age-dependent manner (all P＜ 0.05). However, comparisons among the control groups, only the age-dependent downregulation of LRP-1 were observed in hippocampus(P＜0.05), but other indicators had no significant differences (P＞0.05). Conclusion: In the hippocampus of APP/PS1 double-transgenic mice, the expressions of PTK2B, Aβ1-42 and p-Tau/Tau are upregulated, LRP-1 is downregulated, while cognitive and behavioral ability is decreased, and such changes are presented in a time-dependent manner.

Effects of on behavior and blood-brain barrier in Alzheimer's disease mice / 浙江大学学报·医学版

To investigate the effects of on behavior and blood brain barrier (BBB) in Alzheimer's disease mice. Thirty-eight 4-month-old APP/PS1 double transgenic mice were randomly divided into three groups: model group, low-dose group and high-dose group. Saline, and 12 g·kg·d were given to each group by continuous gavage once a day for respectively. The changes in activities of daily live and fear conditioning memory behavior of mice were examined by nesting behavior test and fear conditioning test, respectively. The β-amyloid protein (Aβ) depositions in cortex and hippocampal CA1 area of mice were detected by thioflavin T staining. The CD34 and activities fibrinogen (Fib) immunofluorescence double staining were used to determine the vascular endothelial integrity and BBB exudation. Compared with model mice, activities of daily live were significantly improved in low-dose and high-dose groups (both <0.01), the fear memory ability was significantly increased in high-dose group (<0.01). The amount of Aβ deposition in cortex and hippocampal CA1 decreased significantly in high-dose group, the area ratio decreased significantly; the area ratio of Aβ deposition in hippocampal CA1 region in low-dose group also decreased (all <0.05). The proportions of CD34 positive area of cortex in low and high dose groups increased, the percentage of fibrinogen positive area decreased (all <0.05). The proportion of CD34 positive area in hippocampal CA1 region in high-dose group was significantly increased, the percentage of fibrinogen positive area decreased significantly (both <0.05). especially high-dose can improve the activities of daily live and fear conditioning memory function of APP/PS1 mice, reduce the deposition of Aβ in brain. The mechanism may be related to the reduction of BBB permeability and the protection of the integrity of BBB.

Evolving Models and Tools for Microglial Studies in the Central Nervous System / 神经科学通报·英文版

Microglia play multiple roles in such processes as brain development, homeostasis, and pathology. Due to their diverse mechanisms of functions, the complex sub-classifications, and the large differences between different species, especially compared with humans, very different or even opposite conclusions can be drawn from studies with different research models. The choice of appropriate research models and the associated tools are thus key ingredients of studies on microglia. Mice are the most commonly used animal models. In this review, we summarize in vitro and in vivo models of mouse and human-derived microglial research models, including microglial cell lines, primary microglia, induced microglia-like cells, transgenic mice, human-mouse chimeric models, and microglial replacement models. We also summarize recent developments in novel single-cell and in vivo imaging technologies. We hope our review can serve as an efficient reference for the future study of microglia.

Methyl salicylate lactoside improves spatial memory and learning abilities of Alzheimer' s transgenic mice / 中国药理学通报

Aim To investigate the effect of methyl salicylate lactoside (MSL) on the spatial memory and learning of Alzheimer' s disease mice. Methods APP/PS1 double transgenic mice were used as AD animal model to evaluate behavioral changes by Morris water test. At the end of the experiment the brain tissues were fixed for assessment of A(3 deposition by immunohistochemistry, neuronal function changes by Nissl staining, neuronal morphological changes by transmission electron microscopy. Results The results showed that MSL could improve the spatial learning and memory abilitiesof AD mice by shortening latency time, prolonging time spent in target quadrant and increasing number of crossings of APP/PS1 mice. MSL could reduce partial Aβ deposition, alleviate the damage of nerve cells and improve the ultrastructural lesions of neuropil projections. Conclusion MSL could reduce Aβ deposition and protect neurons through anti-inflammatory effects, thus improving the learning and memory abilities of Alzheimer' s APP/PS1 transgenic mice.

Roles of sodium channel-voltage-gated-beta 2B in learning and memory improvements of transgenic mice with Alzheimer's disease / 中华行为医学与脑科学杂志

Objective:To explore the potential role of amyloid precursor protein (APP) in the sodium-channel-voltage-beta 2B (SCN2B)-mediated improvement of memory and cognitive function in Alzheimer's Disease (AD).Methods:The SCN2B gene knockout mice (SCN2B -/-) were hybridized with APP gene knockout mice (APP -/-), APP gene heterozygous mice (APP +/-) and APP gene transgenic mice (APP +/+), and the tail tissue of the same mouse was genotyped by PCR gene detection.The mice were divided into SCN2B -/-APP -/- group, SCN2B -/-APP +/- group and SCN2B -/-APP +/+ group.The C57BL/6 wild-type mice were Wild type (WT) group, with 9 mice in each group.SCN2B -/-APP -/-, SCN2B -/-APP +/-, SCN2B -/-APP +/+ transgenic mice and the wild-type mice at the age of 6 months, 12 months, and 18 months were tested by Morris water Maze and Y maze test to detect the cognitive function between each group.Meanwhile, SCN2B -/-APP -/-, SCN2B -/-APP +/-, SCN2B -/-APP +/+ transgenic mice aged 6, 12, 18 months and age-match wild-type were selected to detect neuronal processes in hippocampal CA1 region, and the number of neuronal processes in basal and distal regions of hippocampal CA1 region was quantitatively analyzed.SPSS 21.0 statistical software was used for data statistics and analysis.The differences between the two groups were compared and analyzed by independent-sample t test, the comparison between multiple groups was analyzed by one way analysis of variance (ANOVA), and repeated measurement ANOVA was used to analyze behavioral deta. Results:Repeated measurement ANOVA was used to analyze the data of water maze test. The data showed that the interaction effect of escape latency group and time was significant in 18 month old mice ( Ftime×group=3.63, P<0.01). Simple effect analysis showed that compared with SCN2B -/-APP +/- group and SCN2B -/-APP -/-group, the escape latency of mice in SCN2B -/-APP +/+ group was significantly prolonged from day 4 to 6 (4th day: (47.00±2.00)s, (43.11±1.96) s, (41.89±3.06)s, t=-4.16, 1.00, both P<0.05; 5th day: (45.22±2.54) s, (36.33±2.78) s, (37.00±2.45)s, t=-7.08, -0.54, both P<0.05; 6th day: (38.11±2.03)s, (34.11±2.32)s, (33.00±2.91)s, t=-3.90, 0.90, both P<0.05). The residence time in the target quadrant was shortened((18.00±1.73)s, (25.56±1.33)s, (24.33 ±1.94)s; t=10.37, 1.56, both P<0.05). (2) Y-maze results showed that compared with SCN2B -/-APP +/- group and SCN2B -/-APP -/-group, the number of novel arm entry in 18 month old mice in SCN2B -/-APP +/+ group was decreased((50.22±3.68), (57.22±3.74), (58. 44±5.14) ; t=3.40, -0.48, both P<0.05), and the residence time of stay in the new arm was reduced((10.89±0.62)min, (14.33±0.59)min, (13.89±0.74)min; t= 8.16, 0.44, both P<0.05), and the distance of movement in the new arm was significantly reduced ((37.26±2.01)m , (45.67±2.45)m , (46.11±3.27)m ; t=7.81, 0.91, both P<0.05). (3) Golgi staining showed that SCN2B -/-APP +/- group and SCN2B -/-APP -/-group, the number of apical dendrites in hippocampal neurons of 18 month old mice in SCN2b -/-App +/+ group(number of apical dendrites: (1.78±0.37), (3.67±0.81), (3.00±1.21); t=3.36, 1.41, both P<0.05) and the number of basal dendrites (the number of basal dendrites: (1.11±0.50), (3.11±0.50), (2.56±0.69); t=4.06, 1.21, both P<0.05). Conclusion:SCN2B knockdown can improve the ability of spatial learning and memory in aged mice.Overexpression of APP can partially offset the improvement of cognitive function caused by SCN2B knockdown, and may be affected by the number of basal and distal processes of neurons in the hippocampal CA1 region of the mice.

Establishment of a vimentin knockout and HIV-1 gp120 transgenic mouse model / 南方医科大学学报

OBJECTIVE@#To construct a HIV-1 gp120 transgenic mice (gp120 Tg) with vimentin (VIM) gene knockout.@*METHODS@#Female HIV-1 gp120 Tg mice were mated to VIM heterozygote mice (F0). All the offspring mice were derived from these original founders so that both genotypes had the same mixed genetic background. The F1 mice were bred to generate of VIM, VIM, VIM/gp120 Tg and VIM/gp120 Tg mice. PCR was performed for genotyping of the mice, and the expressions of VIM and gp120 in the brain tissues were examined using immunoblotting.@*RESULTS@#The results of PCR showed the presence of the target bands in VIM, VIM, VIM/gp120 Tg and VIM/gp120 Tg mice. In VIM/gp120 Tg mice, gp120 expression was detected throughout the brain regions while no VIM expression was detected.@*CONCLUSIONS@#We generated gp120 transgenic mouse models with VIM gene knockout, which facilitate the exploration of the role of VIM in gp120-induced neurotoxicity.

Effect of Gastrodiae Rhizoma Powder on Prevention of Dementia and Oxidation Resistance in Mice / 中国实验方剂学杂志

Objective::To study whether long-term administration of Gastrodiae Rhizoma powder can improve the learning and memory ability of APPswe/PSldE9 double transgenic (APP/PS1) Alzheimer' s disease(AD) model mice and delay the progress of AD whether these effects are related to the regulation of antioxidant stress pathway in Kelch-like epoxylopropylamine-related protein 1(Keap1)-nuclear factor E2 related factor 2 (Nrf2)/heme oxygenase(HO)-1, and further explore the neuroprotective mechanism of Gastrodiae Rhizoma powder and its role in the prevention and treatment of AD. Method::APP/PS1 double transgenic mice model, the mice consisted of five groups: normal, normal administration group, model group, Gastrodiae Rhizoma powder prevention group, Gastrodiae Rhizoma powder treatment group.The mice in the normal administration group and the Gastrodiae Rhizoma powder prevention group were given the same dose of Gastrodiae Rhizoma powder (1.5 g·kg-1) daily at the age of 8 weeks.The normal group and model group were given the same amount of normal saline at the same time, until 24 weeks old, Morris water maze was used to test the learning and memory ability of mice, and the treatment group was treated with Gastrodiae Rhizoma powder at 22 weeks old.The mice were given the same dose of Gastrodiae Rhizoma powder (1.5 g·kg-1) every day for 2 weeks.The number of crossing platform, escape latency and platform residence time of mice were detected by Morris water maze from 24 weeks old to 24 weeks old.RNA, Real-time PCR was extracted from mouse hippocampus to detect the mRNA level of Nrf2, HO-1, Keap1, and Western blot was used to detect the expression of Nrf2, HO-1, Keap1 protein in mouse hippocampus. Result::Compared with normal group, the water maze test showed that the learning and memory ability of model group was lower than that of the model group (P<0.01), and the learning and memory ability of Gastrodiae Rhizoma powder prevention group and Gastrodiae Rhizoma powder treatment group was significantly higher than that of model group (P<0.01). Compared with normal group, the levels of Nrf2, HO-1 and protein in the hippocampus in model group decreased in varying degrees (P<0.05). Compared with model group, Gastrodiae Rhizoma powder prevented Nrf2, in the hippocampus of mice in model group.The level of HO-1 in mRNA and protein increased in different degrees (P<0.05, P<0.01). Levels of Nrf2, HO-1 mRNA in Gastrodiae Rhizoma powder treatment group was significantly higher than that in Gastrodiae Rhizoma powder group (P<0.05). There was no significant difference in the expression of Nrf2, HO-1 protein.There was no significant difference in mRNA and protein levels of Keap1 among different groups. Conclusion::Morris water maze test and other results showed that Gastrodiae Rhizoma powder could improve the learning and memory ability of APP/PS1 mice, and it may enhance the expression of downstream antioxidant genes by regulating Keap1-Nrf2/HO-1 pathway.And then improve the learning and memory ability of APP/PS1 mice.

Effects of epigallocatechin-3-gallate on cognitive function and hippocampal autophagy in APP/PSI transgenic mice / 中国药理学通报

Aim To explore mechanism of epigallocatechin-3-gallate (EGCG) on alleviation of hippocampal neuronal autophagy in APP/PSI transgenic mice. Methods 8-month old APP/PSI transgenic mice were randomly divided into three groups;model group (Tg), EGCG low dose group (Tg/EGCG-L), high dose group (Tg/EGCG-H). C57BL/6J mice were utilized as control. Learning and memory were detected by Morris water maze test. The hippocampal ULK1, P62, LC3 I I / LC3 I,mT0R and Aß M2 expressions were detected by Western blot, immunohistochemical staining and ELISA. Results Compared with NT mice, Tg mice showed a marked prolongation of the escape latency in MWM test (P <0. 05). Decreased ULK1 expression and increased P62, LC3 II/LC3 I and A ßM 2 were detected (P < 0. 05). EGCG-treated group showed marked improvement of all these abnormal changes (P < 0. 05). Conclusions EGCG treatment is able to improve cognitive function, which may be attributed to ameliorated autophagic networks dysfunction and reduced Aß plaques in the the hippocampi of APP/PS1 transgenic mice.

CCAAT/enhancer-binding protein alpha (CEBPA) gene haploinsufficiency does not alter hematopoiesis or induce leukemia in Lck-CALM/AF10 transgenic mice

Although rare, CALM/AF10 is a chromosomal rearrangement found in immature T-cell acute lymphoblastic leukemia (T-ALL), acute myeloid leukemia, and mixed phenotype acute leukemia of T/myeloid lineages with poor prognosis. Moreover, this translocation is detected in 50% of T-ALL patients with gamma/delta T cell receptor rearrangement, frequently associated with low expression of transcription factor CCAAT/enhancer-binding protein alpha (CEBPA). However, the relevance of CEBPA low expression for CALM/AF10 leukemogenesis has not yet been evaluated. We generated double mutant mice, which express the Lck-CALM/AF10 fusion gene and are haploinsufficient for the Cebpa gene. To characterize the hematopoiesis, we quantified hematopoietic stem cells, myeloid progenitor cells, megakaryocyte-erythrocyte progenitor cells, common myeloid progenitor cells, and granulocyte-macrophage progenitor cells. No significant difference was detected in any of the progenitor subsets. Finally, we tested if Cebpa haploinsufficiency would lead to the expansion of Mac-1+/B220+/c-Kit+ cells proposed as the CALM/AF10 leukemic progenitor. Less than 1% of bone marrow cells expressed Mac-1, B220, and c-Kit with no significant difference between groups. Our results showed that the reduction of Cebpa gene expression in Lck-CALM/AF10 mice did not affect their hematopoiesis or induce leukemia. Our data corroborated previous studies suggesting that the CALM/AF10 leukemia-initiating cells are early progenitors with lymphoid/myeloid differentiating potential.

Tiaoxin Recipe, a Chinese herbal formula, inhibits microRNA-34a expression in the APPswe/PS1ΔE9 mouse model of Alzheimer's disease / 中西医结合学报

OBJECTIVE@#To investigate the effect and underlying mechanisms of Tiaoxin Recipe (a Chinese herbal formula) treatment on Alzheimer's disease (AD).@*METHODS@#Twelve-week-old APPswe/PS1ΔE9 (APP/PS1) double transgenic mice were used as a model of AD-afflicted mice. One group of mice was treated with Tiaoxin Recipe by gastrogavage for 12 weeks, while two other groups were given intraperitoneal injections of nicotinamide adenine dinucleotide or FK866 for 4 weeks. Morris water maze and thioflavin S staining tests were performed to evaluate cognitive impairment and amyloid plaque deposition, respectively. Serum amyloid-β1-42 (Aβ1-42) content was detected using an enzyme-linked immunosorbent assay, and quantitative reverse transcription-polymerase chain reaction was performed to examine the expression levels of microRNA-34a (miR-34a) in cortex and hippocampus samples of the study mice.@*RESULTS@#Compared with the normal control group, the memory and learning abilities of the APP/PS1 model group were found to be impaired (P < 0.01), as shown by the increased levels of senile plaque deposition in cortex and hippocampus (P < 0.01), miR-34a expression (P < 0.01) and serum Aβ1-42 content (P < 0.01). Treatment with Tiaoxin Recipe significantly reduced memory impairment (P < 0.01) by reducing amyloid plaque accumulation in cortex and hippocampus (P < 0.01), miR-34a expression (P < 0.01) and serum Aβ1-42 content (P < 0.01) in APP/PS1 mice.@*CONCLUSION@#Tiaoxin Recipe is a viable complementary or alternative therapeutic treatment that is capable of delaying the development of early-stage AD by inhibiting the expression of miR-34a.

Generation of a novel HBeAg transgenic mice using CRISPR/Cas9 technique / 南方医科大学学报

OBJECTIVE@#To generate a new strain of HBeAg transgenic mice using CRISPR/Cas9 technique.@*METHODS@#Hepatitis B virus (HBV) HBeAg gene was cloned and inserted in the pliver-HBeAg expression frame at the site of Rosa26 gene using CRISPR/Cas9 and homologous recombination techniques to construct the pliver-HBeAg expression vector containing HBeAg gene. The linear DNA fragment containing HBeAg gene was obtained by enzyme digestion. Cas9 mRNA, gRNA and the donor vector were microinjected into fertilized eggs of C57BL/6J mice, which were then transplanted into the uterus of C57BL/6J female surrogate mice to obtain F0 generation mice. The F0 generation mice were identified by long fragment PCR to obtain F0 transgenic mice with HBeAg gene. The positive F0 generation mice were bred with wild-type C57BL/6J mice to produce the F1 mice, which were identified by PCR and sequencing. The positive F1 transgenic mice carrying HBeAg gene were backcrossed until the homozygous offspring transgenic mice were obtained. The genotypes of the offspring mice were identified. The expressions of HBeAg and HBeAb in the heterozygous and homozygous HBeAg transgenic mice were detected by automatic chemiluminescence immunoassay, immune colloidal gold technique and immunohistochemistry method.@*RESULTS@#A total of 56 F0 mice were obtained, and 2 of them carried homologous recombined HBeAg gene. Six positive F1 mice were obtained, from which 22 homozygous and 29 heterozygous F2 generation HBeAg transgenic mice were obtained. High concentration of HBeAg protein was detected in the peripheral blood of all the positive HBeAg transgenic mice without HBeAb expression. HBeAg expression was detected in the hepatocytes of HBeAg transgenic mice.@*CONCLUSIONS@#We obtained a new strain of HBeAg transgenic mice with stable expression of HBeAg in the hepatocytes and immune tolerance to HBeAg using CRISPR/Cas9 technique, which provide a new animal model for studying HBV.

Effects of gender and age on protein secretion in saliva of transgenic mice expressing human nerve growth factor / 生物工程学报

Nerve growth factor (NGF) can promote the development, differentiation and regeneration of neurons. Recently, in order to efficiently produce human NGF (hNGF) drugs with better efficacy, we created transgenic mice expressing hNGF specifically in their salivary glands, and purified highly active hNGF protein from their saliva. Some studies reported that the NGF secretion in mouse saliva is affected by gender and age. Here, in order to select hNGF transgenic mice with high NGF secretion for saliva collection and hNGF purification, we divided transgenic mice into 4 groups, including 28-day-old young males and females, 63-day-old adult males and females. We compared their saliva volume, total salivary protein amount, salivary mNGF protein amount and salivary hNGF protein amount. The results showed that the saliva volume as well as amounts of total salivary protein, salivary mNGF protein and salivary hNGF protein secreted by 63-day-old transgenic mice were significantly higher than those secreted by sex-match 28-day-old transgenic mice, and the salivary hNGF protein amount secreted by male transgenic mice at the age of 63 days was significantly higher than that of female transgenic mice at the same age; Among 4 groups of mice, 63-day-old male transgenic mice secreted the highest salivary hNGF content, which was about 46 times higher than that secreted by the 28-day-old female transgenic mice. Therefore, 63-day-old male transgenic mice should be selected for saliva collection and hNGF purification.

Influence of PRKAG2 gene G100S novel mutation on adenosine monophosphate-activated protein kinase activity in cardiomyocytes of mice / 第二军医大学学报

Objective To explore the effect of PRKAG2 gene G100S mutation in cystathionine β-synthase (CBS) region on adenosine monophosphate-activated protein kinase (AMPK) activity in cardiomyocytes of mice. Methods A human PRKAG2 (G100S) transgenic mouse model was established. Four-week-old and 12-week-old transgenic mice, and 4-week-old and 12-week-old wildtype littermate were randomly selected from N4 generation mice (n＝6). The activity of AMPK in mouse cardiomyocytes was detected by phosphorylation assay kit. The difference of AMPK activity was compared between transgenic mice and wildtype littermate, and the changes of the activity of AMPK with the increase of age were observed in transgenic mice. Results The AMPK activities in cardiomyocytes of 4-week-old and 12-week-old transgenic mice were significantly lower than those of the wildtype littermate (0.042±0.013 vs 0.063±0.013, and 0.032±0.008 vs 0.062±0.018), and the differences were significant (P＝ 0.019, P＝0.004). There was no significant difference in the AMPK activity of cardiomyocytes between 4-week-old and 12-week-old transgenic mice (P＝0.135). Conclusion The PRKAG2 gene G100S mutation can cause a reduction of AMPK activity in cardiomyocytes of transgenic mice, and AMPK activity does not significantly increase or decrease with the growth of the transgenic mice.