Establishment of a C57BL/6 mouse model simulating transurethral thulium laser vaporization prostatectomy / 中华泌尿外科杂志

Objective:To construct a C57BL/6 mouse model of simulating transurethral thulium laser vaporization prostatectomy.Methods:Twelve male C57BL/6 mice were selected to undergo transvesical vaporization resection of the urothelium covering the urethra of the prostate using thulium laser. The urethral tissue of the prostate was retrieved on the 1st, 3rd, 5th, and 7th days after the surgery. HE staining was used to observe the process of re-epithelialization of the urethral wound of the prostate. Immunohistochemical (IHC) staining was used to detect whether the re-epithelialized cells of the urethral wound of the prostate expressed urothelin Ⅲ (UPⅢ).Results:On the first day after surgery, HE staining showed complete destruction to the urothelium covering the urethra of the prostate, with a large amount of coagulative necrotic tissue on the wound surface, and IHC staining showed no expression of UPⅢ on the wound surface. On the 3rd day after surgery, HE staining showed that there were still no regenerated epithelial cells on the wound surface, with coagulation necrosis tissue significantly reduced, and the urethral cavity was clearly visible. And IHC staining showed no expression of UPⅢ on the wound surface. On the 5th day after surgery, HE staining showed 1-2 layers of regenerated epithelial cells lacking cell polarity on the wound surface, and IHC staining showed that the regenerated epithelial cells expressed UPⅢ. On the 7th day after surgery, HE staining showed 4-6 layers of polar regenerated epithelial cells on the wound surface, and IHC staining showed the multiple layers of regenerated epithelial cells expressing UPⅢ.Conclusions:Based on the simulation of transurethral thulium laser vaporization resection of the prostate, the thulium laser and ultra micro endoscope system were used to vaporize the urothelium covering the urethra of the prostate, and the process of urethral re-epithelialization of the prostate can be observed after surgery. The establishment of the C57BL/6 mouse model simulating thulium laser vaporization prostatectomy provides a new research platform for studying the mechanism of wound repair after prostatectomy.

The antitumor effect of cisplatin chemotherapy promoted by Taohong Siwu Decoction on mice with lung adenocarcinoma / 中国药理学通报

Aim To study the antitumor effect of cispl-atin ( DDP) chemotherapy promoted by Taohong Siwu Decoction (TSD) on mice with lung adenocarcinoma mice. Methods Lewis lung carcinoma cell line was used to make homologous lung adenocarcinoma trans¬plantation mouse model. Normal control, Model, TSD, DDP, TSD + DDP groups were set up. The change of transplanted tumor volume after administration was observed, the weight of transplanted tumor was weighed, the expression of Ki67 in transplanted tumor tissue was detected by immunohistochemistry, TUNEL was detected by fluorescence staining, Bcl-2, Bax, cleaved Caspase-3 and cleaved Caspase-9 were detected by immunoblotting, and the content of D-dirtier in plasma was measured by ELISA. Results DDP plus TSD significantly inhibited the growth of transplanted tumor. Ki67 expression in tumor tissue was lower than that in DDP group (28. 3% ±3. 1% vs 40. 3% ±2.1% ). The combined use of TSD and DDP significantly promoted the apoptosis level of transplanted tumor. The positive rate of TUNEL was significantly higher than that of DDP group (41. 0% ±3.0% vs 30.7% ± 4.5%). Bax, cleaved Caspase-3 and cleaved Caspase-9 expressions in tumor tissue were also higher than those of DDP group, while the expression of Bcl-2 was significantly lower than that of DDP group. Moreover, we found a significant interaction between TSD and DDP on the expression of four apoptotic proteins ( P < 0.05 ) . The plasma D-dimer content in TSD + DDP group was significantly lower than that in DDP group (188. 50 ± 28. 46 vs 269.80 ± 35.92) μg • L

Construction of a Mouse Model for Myeloproliferative Neoplasms and an Evaluation System / 中国实验血液学杂志

OBJECTIVE@#To construct a myeloproliferative neoplasms (MPN) transplanted mouse model with JAK2-V617F, MPLW515L or CALR-Type I gene mutation, and establish a systematic evaluation system to verify the success of model construction.@*METHODS@#The bone marrow c-kit+ cells of the mice were obtained by the following steps: The mice were killed by cervical dislocation, the femur, tibia and ilium were separated, and the bone marrow cells were collected. The c-kit+ cells were sorted after incubation with CD117 magnetic beads. The method of constructing mouse primary mutant cells is as follows: A gene mutation vector with a GFP tag was constructed by the retroviral system, and the retroviral vector was packaged into the Platinum-E cells to obtain the virus supernatant, and then used it to infect the c-kit+ cells of mice. The MPN mouse model was constructed as follows: the mouse primary c-kit+ cells containing the mutant genes were collected after infection, and then transplanted them via the tail vein into the female recipient mice of the same species which were irradiated with a lethal dose of gamma rays (8.0 Gy). The MPN mouse model was evaluated as follows: After transplantation, the peripheral blood of the mice was regularly collected from the tail vein to perform the complete blood count test, and the size of spleen and the degree of bone marrow fibrosis were estimated.@*RESULTS@#The mouse c-kit+ cells with the mutant genes were successfully obtained from the bone marrow. MPN mouse model was successfully constructed: The peripheral blood cells of the MPN-transplanted mice carried exogenous implanted GFP-positive cells, and the white blood cells (WBC), platelet (PLT) and hematocrit (HCT) were all increased; the body weight loss, and the water and food intake were reduced in the transplanted mice; further pathological analysis showed that the transplanted mice displayed splenomegaly and bone marrow fibrosis. These results suggested that the MPN mouse model was successfully constructed. According to the common and different characteristics of the three MPN mouse model, a preliminary evaluation system for judging the success of MPN mouse model construction was summarized, which mainly included the following indicators, for example, the proportion of GFP-positive cells in the peripheral blood of mice; WBC, PLT and HCT; the degree of spleen enlargement and the bone marrow fibrosis.@*CONCLUSION@#The MPN mouse model with JAK2-V617F, MPLW515L or CALR-Type I gene mutation is successfully established by retroviral system, which can provide an important experimental animal model for the research of MPN pathogenesis and drug-targeted therapy.

Disrupted Maturation of Prefrontal Layer 5 Neuronal Circuits in an Alzheimer's Mouse Model of Amyloid Deposition / 神经科学通报·英文版

Mutations in genes encoding amyloid precursor protein (APP) and presenilins (PSs) cause familial forms of Alzheimer's disease (AD), a neurodegenerative disorder strongly associated with aging. It is currently unknown whether and how AD risks affect early brain development, and to what extent subtle synaptic pathology may occur prior to overt hallmark AD pathology. Transgenic mutant APP/PS1 over-expression mouse lines are key tools for studying the molecular mechanisms of AD pathogenesis. Among these lines, the 5XFAD mice rapidly develop key features of AD pathology and have proven utility in studying amyloid plaque formation and amyloid β (Aβ)-induced neurodegeneration. We reasoned that transgenic mutant APP/PS1 over-expression in 5XFAD mice may lead to neurodevelopmental defects in early cortical neurons, and performed detailed synaptic physiological characterization of layer 5 (L5) neurons from the prefrontal cortex (PFC) of 5XFAD and wild-type littermate controls. L5 PFC neurons from 5XFAD mice show early APP/Aβ immunolabeling. Whole-cell patch-clamp recording at an early post-weaning age (P22-30) revealed functional impairments; although 5XFAD PFC-L5 neurons exhibited similar membrane properties, they were intrinsically less excitable. In addition, these neurons received smaller amplitude and frequency of miniature excitatory synaptic inputs. These functional disturbances were further corroborated by decreased dendritic spine density and spine head volumes that indicated impaired synapse maturation. Slice biotinylation followed by Western blot analysis of PFC-L5 tissue revealed that 5XFAD mice showed reduced synaptic AMPA receptor subunit GluA1 and decreased synaptic NMDA receptor subunit GluN2A. Consistent with this, patch-clamp recording of the evoked L23>L5 synaptic responses revealed a reduced AMPA/NMDA receptor current ratio, and an increased level of AMPAR-lacking silent synapses. These results suggest that transgenic mutant forms of APP/PS1 overexpression in 5XFAD mice leads to early developmental defects of cortical circuits, which could contribute to the age-dependent synaptic pathology and neurodegeneration later in life.

Schisandrae Fructus oil-induced elevation in serum triglyceride and lipoprotein concentrations associated with physiologic hepatomegaly in mice

Objective: To investigate hypertriglyceridemia and hepatomegaly caused by Schisandrae Sphenantherae Fructus (FSS) and Schisandra chinensis Fructus (FSC) oils in mice. Methods: Mice were orally administered a single dose of Schisandrae Fructus oils. Serum and hepatic triglyceride (TG), triglyceride transfer protein (TTP), apolipoprotein B48 (Apo B48), very-low-density lipoprotein (VLDL), hepatocyte growth factor (HGF), alanine aminotransfease (ALT) and liver index were measured at 6-120 h post-dosing. Results: FSS and FSC oil caused time and dose-dependent increases in serum and hepatic TG levels, with maximum increases in the liver (by 297% and 340%) at 12 h post-dosing and serum (244% and 439%) at 24-h post-dosing, respectively. Schisandrae Fructus oil treatments also elevated the levels of serum TTP by 51% and 63%, Apo B48 by 152% and 425%, and VLDL by 67% and 38% in mice, respectively. FSS and FSC oil treatments also increased liver mass by 53% and 55% and HGF by 106% and 174%, but lowered serum ALT activity by 38% and 22%, respectively. Fenofibrate pre/ co-treatment attenuated the FSS and FSC oil-induced elevation in serum TG levels by 41% and 49% at 48 h post-dosing, respectively, but increased hepatic TG contents (by 38% and 33%, respectively) at 12 h post-dosing. Conclusions: Our findings provide evidence to support the establishment of a novel mouse model of hypertriglyceridemia by oral administration of FSS oil (mainly increasing endogenous TG) and FSC oil (mainly elevating exogenous TG).

Protective effects and mechanism of icariin against vascular function in diabetic mice / 中国药科大学学报

@#To explore the effects and molecular mechanism of icariin on the vascular function of mice with type 1 diabetes induced by alloxan, type 1 diabetic mice model was established by intraperitoneal injection with 200 mg/kg alloxan.After oral administration with icariin (60, 120 mg/kg) daily for 2 weeks, blood glucose, body weight, food intake and water intake were detected.To evaluate the impact of icariin on the function of isolated vascular ring contraction and relaxation, thoracic aortas of mice were removed and the Ach-induced vascular ring relaxation, Phe-induced vascular ring contraction, SNP-induced vascular ring relaxation and KCl-induced vascular ring contraction response were detected.To further confirm the mechanism of icariin to improve vascular function, human umbilical vein endothelial cells (HUVECs) were induced by high glucose (HG) in vitro.Western blot was used to detect the effect of icariin on eNOS, p-eNOS, p38 MAPK and p-p38 MAPK expressions in HG-induced human umbilical vein endothelial cells (HUVECs).The results indicated that icariin significantly ameliorated the weight loss and dampened the increase in water intake of the diabetic mice.Meanwhile, icariin had a certain ameliorative effect on blood glucose and food intake without significant difference.The results of isolated thoracic aortas vascular rings contraction and vasodilation function indicated that icariin significantly improved Phe-induced vascular contraction and Ach‐induced vascular relaxation.Meanwhile, icariin had a certain ameliorative effect on KCl-induced vascular contraction response without significant difference.However, no significant change was observed on endothelium‐independent vascular rings relaxation response induced by SNP after treatment with icariin.Results of Western blot showed that icariin inhibited the expression of p-p38 MAPK and induced expression of p-eNOS in the high glucose-induced HUVECs cell model.Therefore, icariin may attenuate alloxan-induced type 1 diabetic mice vascular diastolic function by inhibiting expression of p-p38 MAPK and inducing expression of p-eNOS.

Effect of Gandou Decoction on Mitophagy in Toxic Milk （TX） Mouse Model of Wilson Disease Based on Pink1/Parkin Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the effects of Gandou decoction （GDD） on the mitophagy of hippocampal neurons in toxic milk （TX） mouse model of Wilson disease and explore the protective mechanism of GDD against neuron injury through the PTEN induced kinase 1 （Pink1） /E3 ubiquitin ligase （Parkin） pathway. MethodSixty mice were randomly divided into a blank group， a model group， a penicillamine group （0.09 g·kg-1）， and low- （5.5 g·kg-1）， medium- （11 g·kg-1）， and high-dose （22 g·kg-1） GDD groups， and treated correspondingly by gavage for 8 weeks. Morris water maze， traction test， and pole test were used for the evaluation of animal behaviors. Hematoxylin-eosin （HE） staining and transmission electron microscopy were used to observe cell apoptosis， ultrastructure， autophagy， and mitochondrial structure. The levels of superoxide dismutase （SOD）， reactive oxygen species （ROS）， and malondialdehyde （MDA） were detected by enzyme-linked immunosorbent assay （ELISA）. Real-time fluorescence-based quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of Pink1， Parkin， autophagy-associated protein Beclin-1， microtubule-associated protein 1 light chain 3Ⅱ （LC3Ⅱ）， and p62. Western blot was conducted to detect the protein expression of Pink1， Parkin， Beclin-1， LC3Ⅱ/Ⅰ， and p62. ResultCompared with the blank group， the model group showed prolonged escape latency， decreased times of platform crossing， lower score in the traction test， and longer pole climbing time （P<0.01）. Compared with the model group， the medium- and high-dose GDD groups and the penicillamine group showed shortened escape latencies， increased times of platform crossing， higher scores in the traction test， and shortened pole climbing time （P<0.01）. Compared with the blank group， the model group displayed severely damaged neurons and increased autophagosomes. Compared with the model group， the medium- and high-dose GDD groups and the penicillamine group showed improved neuron damage and reduced autophagosomes. The levels of ROS and MDA were higher and SOD was lower in the model group than those in the blank group （P<0.01）， while the levels of the above indicators were reversed by GDD intervention as compared with the model group （P<0.01）. Compared with the blank group， the model group exhibited up-regulated mRNA and protein expression of Pink1， Parkin， LC3Ⅱ， and Beclin-1 and down-regulated p62 （P<0.05）. Compared with the model group， the medium- and high-dose GDD groups showed reduced mRNA and protein expression of Pink1， Parkin， LC3Ⅱ， and Beclin-1 and increased p62 （P<0.05， P<0.01）. ConclusionGDD can significantly inhibit the excessive mitophagy in neurons of TX mice and protect neurons from damage. The mechanism may be related to the regulation of the Pink1/Parkin pathway.

Ameliorative Effect of Gramine on 2，4-Dinitrochlorobenzene-Induced Atopic Dermatitis in Mice / 中国实验方剂学杂志

ObjectiveTo explore the pharmacodynamic effect of gramine on 2，4-dinitrochlorobenzene （DNCB）-induced atopic dermatitis （AD） in mice and its potential mechanism. MethodThe mice were divided into the normal control group， model group， dexamethasone （0.05 g·kg-1） group， and high- and low-dose （0.12，0.06 g·kg-1） gramine groups. Mice in all groups except for the normal control group were stimulated with DNCB， followed by medication 13 d later. The changes in skin lesions were then observed， and the skin thickness， moisture content， and transepidermal water loss （TWEL） in each group were measured. The pathological changes in skin lesions were observed by hematoxylin-eosin （HE） staining， and the effects of drugs on CD4+/CD8+T-cell ratio in the spleen were detected by flow cytometry. The levels of immunoglobulin E （IgE）， interleukin （IL）-4， and IL-6 in serum were detected by enzyme-linked immunosorbent assay （ELISA）， and the changes in serum alanine aminotransferase （ALT）， aspartate aminotransferase （AST）， blood urea nitrogen （BUN）， and creatinine （CRE） by microplate method. The mRNA expression levels of inflammatory cytokines γ-interferon（IFN-γ）， IL-13， IL-17， IL-1β， IL-6， and tumor necrosis factor-α （TNF-α） in skin lesions were assayed by real-time polymerase chain reaction （Real-time PCR）， and the protein expression levels of nuclear transcription factor -κB (NF-κB) and NF-κB inhibitory protein α (IκBα) in skin lesions by Western blot. ResultCompared with the normal control group， the model group showed skin edema， erythema， scab， scratch， and lymphocyte and neutrophil infiltration， decreased skin moisture content， as well as increased skin thickness， TWEL （P<0.01）， spleen index， CD4+/CD8+ T-cell ratio in the spleen （P<0.05）， mRNA expression of IFN-γ， IL-13， IL-17， IL-1β， IL-6， and TNF-α in the skin lesions （P<0.05）， serum contents of IgE， IL-4， and IL-6 （P<0.05）， and protein expression of IκBα and NF-κB in skin lesions （P<0.05）. Compared with the model group， dexamethasone and gramine at different doses alleviated skin erythema， scale， scab， and inflammatory cell infiltration， elevated skin moisture content， inhibited skin thickening and TWEL， and decreased spleen index， CD4+/CD8+T-cell ratio in the spleen， mRNA expression of inflammatory factors in the skin lesions， serum contents of IgE and inflammatory factors， and protein expression of IκBα and NF-κB in skin lesions， especially in the dexamethasone group and the high- dose gramine group（P<0.05，P<0.01）. ConclusionGramine can inhibit the expression of related inflammatory factors and regulate the immune function of AD mice via the IκBα/NF-κB pathway， enabling it become a potential drug for treating AD.

Effects of the ITGA2B Nonsense Mutation (c.2659C > T, p.Q887X) on Platelet Function in a Mouse Model of Glanzmann's Thrombasthenia Generated with CRISPR/Cas9 Technology / 中国实验血液学杂志

OBJECTIVE@#To construct a mouse model of Glanzmann's thrombasthenia (GT) with ITGA2B c.2659 C>T (p.Q887X) nonsense mutation by CRISPR/Cas9 technology, and then further explore the expression and function of glycoprotein αIIbβ3 on the surface of platelet membrane.@*METHODS@#The donor oligonucleotide and gRNA vector were designed and synthesized according to the ITGA2B gene sequence. The gRNA and Cas9 mRNA were injected into fertilized eggs with donor oligonucleotide and then sent back to the oviduct of surrogate mouse. Positive F0 mice were confirmed by PCR genotyping and sequence analysis after birth. The F1 generation of heterozygous GT mice were obtained by PCR and sequencing from F0 bred with WT mice, and then homozygous GT mice and WT mice were obtained by mating with each other. The phenotype of the model was then further verified by detecting tail hemorrhage time, saphenous vein bleeding time, platelet aggregation, expression and function of αIIbβ3 on the surface of platelet.@*RESULTS@#The bleeding time of GT mice was significantly longer than that of WT mice (P<0.01). Induced by collagen, thrombin, and adenosine diphosphate (ADP), platelet aggregation in GT mice was significantly inhibited (P<0.01, P<0.01, P<0.05). Flow cytometry analysis showed that the expression of αIIbβ3 on the platelet surface of GT mice decreased significantly compared with WT mice (P<0.01), and binding amounts of activated platelets to fibrinogen were significantly reduced after thrombin stimulation (P<0.01). The spreading area of platelet on fibrinogen in GT mice was significantly smaller than that in WT mice (P<0.05).@*CONCLUSION@#A GT mouse model with ITGA2B c.2659 C>T (p.Q887X) nonsense mutation has been established successfully by CRISPR/Cas9 technology. The aggregation function of platelet in this model is defective, which is consistent with GT performance.

Establishment of a Mouse Model of Acquired Aplastic Anemia Mediated by Cyclophosphamide Combined with Cyclosporine / 中国实验血液学杂志

OBJECTIVE@#To establish a stable mouse model of acquired aplastic anemia.@*METHODS@#Female BALB/C mice aged 6 months were intraperitoneally injected with cyclophosphamide and cyclosporine for 14 days. The number of peripheral blood cells, the concentration of hemoglobin, the number of bone marrow nucleated cells, bone marrow smear, bone marrow pathological sections and other indexes were observed.@*RESULTS@#In BALB/C mice injected intraperitoneally with cyclophosphamide and cyclosporine, the number of peripheral blood cells and the concentration of hemoglobin were significantly decreased, especially the white blood cells and platelets. Bone marrow smear showed a significant decrease in the number of nucleated cells and bone marrow hyperplasia. Bone marrow pathology showed decreased hematopoietic cells and increased non-hematopoietic cells such as adipocytes.@*CONCLUSION@#The mouse model with intraperitoneal injection of cyclophosphamide and cyclosporine can meet the diagnostic criteria of acquired aplastic anemia, which can be used as a mouse model for the study of the pathogenesis and treatment of acquired aplastic anemia.

Polymerase chain reaction-based assays facilitate the breeding and study of mouse models of Klinefelter syndrome / 亚洲男科学杂志(英文版)

Klinefelter syndrome (KS) is one of the most frequent genetic abnormalities and the leading genetic cause of nonobstructive azoospermia. The breeding and study of KS mouse models are essential to advancing our knowledge of the underlying pathological mechanism. Karyotyping and fluorescence in situ hybridization are reliable methods for identifying chromosomal contents. However, technical issues associated with these methods can decrease the efficiency of breeding KS mouse models and limit studies that require rapid identification of target mice. To overcome these limitations, we developed three polymerase chain reaction-based assays to measure specific genetic information, including presence or absence of the sex determining region of chromosome Y (Sry), copy number of amelogenin, X-linked (Amelx), and inactive X specific transcripts (Xist) levels. Through a combined analysis of the assay results, we can infer the karyotype of target mice. We confirmed the utility of our assays with the successful generation of KS mouse models. Our assays are rapid, inexpensive, high capacity, easy to perform, and only require small sample amounts. Therefore, they facilitate the breeding and study of KS mouse models and help advance our knowledge of the pathological mechanism underlying KS.

Anti-herpes simplex virus effect of aristolochic acids in vitro and in vivo / 中国药理学通报

Aim To investigate the inhibition effects and mechanisms of aristolochic acids(AAs)against herpes simplex virus(HSV)in vitro and in vivo. Methods The cytopathic effect(CPE), plaque assay, indirect immunofluorescence and others were used to explore the anti-HSV effects and mechanisms of aristolochic acid in Vero cells, and the in vivo anti-HSV activity of AAs was evaluated using HSV-1 infected BALB/c mouse model. Results The IC

Optimization and establishment of therapeutic model of Bletilla striata polysaccharide on dextran sodium sulfate-induced ulcerative colitis in mice / 西安交通大学学报(医学版)

【Objective】 To establish the optimal treatment model of Bletilla striata polysaccharide （BSP） on dextran sodium sulfate （DSS）-induced ulcerative colitis （UC） in mice. 【Methods】 We randomly divided 48 male C57BL/6 mice into normal control group， DSS model group （25 g/L DSS）， BSP low-， medium- and high-dose groups （25 g/L DSS + 95， 190， 380 mg/kg BSP）， and salazosulfapyridine （SASP） （25 g/L DSS + 320 mg/kg SASP， positive control） group. Mice in the normal control group drank distilled water freely， while the other groups were given 25 g/L DSS solution to drink freely for 7 days. From the second day， the low-， medium- and high-dose BSP groups and SASP （positive control）group were administered by gavage according to body mass. The normal control group and DSS model group were given the same amount of normal saline once a day for 7 consecutive days. The mice’s blood pressure was recorded every day. Mental state， body mass， stool characteristics and bloody stool were used to calculate the mice’s disease activity index （DAI）. The mice were killed on the 9th day， and their colonic tissues were taken for hematoxylin eosin （HE） staining and histopathological scoring. The expression of tight junction protein Claudin-1 in colonic tissues was detected by Western blotting. 【Results】 Compared with the normal control group， the DSS model group had obvious clinical manifestations， histopathological changes and reduced body weight， increased histopathological score and DAI score （P<0.05）， and decreased expression of tight junction protein Claudin-1 in colon tissue （P<0.05）. Compared with those in DSS model group， the clinical manifestations of UC and colonic mucosal injury in low-， medium- and high-dose BSP groups were improved in varying degrees. The high-dose （380 mg/kg） BSP group had the best effect. The degree of body weight reduction， histopathological score and DAI score in this group were significantly lower than those in DSS model group （P<0.05）， whereas the expression of Claudin-1 increased significantly （P<0.05）. 【Conclusion】 When BSP was administered by gavage at 380 mg/kg， the therapeutic effect on UC mice induced by 25 g/L DSS was the best. This model can be used as an effective one for further studies on Striata Bletilla polysaccharide in UC mice.

Establishment and evaluation of a BALBc mouse model of Burkholderia pseudomallei via nasal infection / 中国热带医学

@#Abstract: Objective To establish an animal model of BALB/c mice infected with Burkholderia pseudomallei through the nose (inhalation route), provides a reliable animal model for the follow-up studies on the virulence of melioidosis and the pathogenesis of acute melioidosis. Methods　The experiment was carried out through infecting with Burkholderia pseudomallei through the nose (inhalation route). The pathophysiological response, visceral pathological damage and bacterial colonization of the mice infected with Burkholderia pseudomallei were observed by gross anatomy, histopathology and tissue homogenate count, and the biological characteristics of the mouse model of acute melioidosis were analyzed accordingly. Then we compared the physiological responses in BALB/c mice between the Burkholderia pseudomallei and non-pathogenic Burkholderia thailandensis. Results　In the model of acute nasal infection with Burkholderia thailandensis, most death happened between the 3rd to 5th day after infection, 3×105-3×106 CFU was the suitable dose for acute fatal melioidosis model of BALB/c mice, and the medium lethal dose was about 3×104-3×105 CFU. Both gross anatomy and tissue HE staining showed that abscesses or necrosis were found in the lung, spleen and liver, especially in the spleen and lung, which was positively correlated with the challenge dose. Viable bacteria was isolated from the blood, lung, spleen and liver of Burkholderia pseudomallei-infected mice, and the bacteria account colonization was related to tissue specificity. The concentration of live bacteria isolated from in the blood was the highest [Log2 value: (10.28±0.34) CFU/mL], and the organ with the maximum quantity of bacteria was the lung [Log2 value: (7.54±2.11) CFU/total organ]. It has been reported that the biological effects of Burkholderia pseudomallei and its homologous non-pathogenic Burkholderia thailandensis were similar at the cellular level, like multi-nuclear giant cell formation and active intracellular replication, while it is still unclarrified in the differences of virulence in mice. In this study, it was proved that Burkholderia thailandensis was not fatal to mice even at a high dose (8×107CFU), or detected from mice infected with it via nasal. Conclusion　We successfully established a reliable BALB/c mouse model (acute lethal model) of melioidosis via nasal infection, described its biological characteristics, and identified the different biological responses between Burkholderia pseudomallei and its homologous non-pathogenic Burkholderia thailandensis in mice.

CRISPR-mediated base editing in mice using cytosine deaminase base editor 4

BACKGROUND: Many human genetic diseases arise from point mutations. These genetic diseases can theoretically be corrected through gene therapy. However, gene therapy in clinical application is still far from mature. Nearly half of the pathogenic single-nucleotide polymorphisms (SNPs) are caused by G:C>A:T or T:A>C:G base changes and the ideal approaches to correct these mutations are base editing. These CRISPR-Cas9-mediated base editing does not leave any footprint in genome and does not require donor DNA sequences for homologous recombination. These base editing methods have been successfully applied to cultured mammalian cells with high precision and efficiency, but BE4 has not been confirmed in mice. Animal models are important for dissecting pathogenic mechanism of human genetic diseases and testing of base correction efficacy in vivo. Cytidine base editor BE4 is a newly developed version of cytidine base editing system that converts cytidine (C) to uridine (U). RESULTS: In this study, BE4 system was tested in cells to inactivate GFP gene and in mice to introduce single-base substitution that would lead to a stop codon in tyrosinase gene. High percentage albino coat-colored mice were obtained from black coat-colored donor zygotes after pronuclei microinjection. Sequencing results showed that expected base changes were obtained with high precision and efficiency (56.25%). There are no off-targeting events identified in predicted potential off-target sites. CONCLUSIONS: Results confirm BE4 system can work in vivo with high precision and efficacy, and has great potentials in clinic to repair human genetic mutations.

One extraction tool for in vitro-in vivo extrapolation?SPME-based metabolomics of in vitro 2D,3D,and in vivo mouse melanoma models / 药物分析学报

Solid phase microextraction(SPME)in combination with high-resolution mass spectrometry was employed for the determination of metabolomic profile of mouse melanoma growth within in vitro 2D,in vitro 3D,and in vivo models.Such multi-model approach had never been investigated before.Due to the low-invasiveness of SPME,it was possible to perform time-course analysis,which allowed building time profile of biochemical reactions in the studied material.Such approach does not require the multiplication of samples as subsequent analyses are performed from the very same cell culture or from the same individual.SPME already reduces the number of animals required for experiment;therefore,it is with good concordance with the 3Rs rule(replacement,reduction,and refinement).Among tested models,the largest number of compounds was found within the in vitro 2D cell culture model,while in vivo and in vitro 3D models had the lowest number of detected compounds.These results may be connected with a higher metabolic rate,as well as lower integrity of the in vitro 2D model compared to the in vitro 3D model resulting in a lower number of compounds released into medium in the latter model.In terms of in vitro-in vivo extrapolation,the in vitro 2D model performed more similar to in vivo model compared to in vitro 3D model;however,it might have been due to the fact that only compounds secreted to medium were investigated.Thus,in further experiments to obtain full metabolome infor-mation,the intraspheroidal assessment or spheroid dissociation would be necessary.

Mechanism of Dahuang Zhechongwan in Inhibiting Silicosis in Mice via p38 MAPK/NF-κB/TGF-β1 Pathway / 中国实验方剂学杂志

Objective:To explore the effects and mechanism of Chinese classical prescription Dahuang Zhechongwan on silicosis in mice. Method:Thirty-six male Kunming mice of SPF grade were randomized into the normal control group， model control group， tetrandrine （Tet， 0.039 mg·kg^-1） group， as well as high- （1.560 g·kg^-1）， medium- （0.780 g·kg^-1）， and low-dose （0.390 g·kg^-1） Dahuang Zhechongwan groups， with six mice in each group. Mice in all groups except for the normal control group underwent static inhalation of silica （SiO₂） dust for 40 consecutive days to induce fibrosis. After 28 days of intervention with corresponding drugs， the mice were sacrificed to collect the serum and lung tissues， with the former used for detecting tumor necrosis factor-<italic>α</italic> （TNF-<italic>α</italic>）， interleukin-1<italic>β </italic>（IL-1<italic>β</italic>）， IL-6， and hydroxyproline （HYP） levels by enzyme-linked immunosorbent assay （ELISA） and the latter for observing the pathological changes. Meanwhile， the protein and mRNA expression levels of p38 mitogen-activated protein kinase （p38 MAPK）， nuclear transcription factor-<italic>κ</italic>B （NF-<italic>κ</italic>B）， transforming growth factor-<italic>β</italic>₁ （TGF-<italic>β</italic>₁）， <italic>α</italic>-smooth muscle actin （<italic>α</italic>-SMA）， Smad2， Smad3， and Smad7 in the lung tissues were determined by Western blot and real-time polymerase chain reaction （Real-time PCR）. Result:Compared with the normal group， the contents of TNF-<italic>α</italic>， IL-1<italic>β</italic>， IL-6 and HYP in the model group were significantly increased， the difference was statistically significant（<italic>P</italic><0.05，<italic>P</italic><0.01）； compared with the model group， the high-dose group of Dahuang Zhechongwan could significantly reduce the contents of TNF-<italic>α</italic>， IL-6 and HYP in the serum of mice（<italic>P</italic><0.05， <italic>P</italic><0.01）， indicating that Dahuang Zhechongwan could reduce the lung inflammation of silicosis mice. At the same time， compared with the normal group， the protein and mRNA expression levels of p38 MAPK， NF-<italic>κ</italic>B p65， TGF-<italic>β</italic>₁， <italic>α</italic>-SMA， Smad2 and Smad3 in the model group were significantly increased（<italic>P</italic><0.05，<italic>P</italic><0.01）， while the protein and mRNA expression levels of Smad7 were significantly decreased（<italic>P</italic><0.01）； compared with the model group， the protein and mRNA expression levels of p38 MAPK， NF-<italic>κ</italic>B p65， TGF-<italic>β</italic>₁， <italic>α</italic>-SMA， Smad2 and Smad3 in the high-dose Dahuang Zhechongwan group were significantly increased the protein and mRNA expression levels were significantly decreased（<italic>P</italic><0.05，<italic>P</italic><0.01）， while Smad7 protein and mRNA expression levels were significantly increased（<italic>P</italic><0.05，<italic>P</italic><0.01）. Conclusion:Dahuang Zhechongwan ameliorates the alveolar inflammation， extracellular matrix （ECM） deposition， and fibrosis in mice with silicosis possibly by regulating the p38 MAPK/NF-<italic>κ</italic>B/TGF-<italic>β</italic>₁ pathway.

Establishment of an Iron-overloaded Mouse Model with Tuberculosis and Analysis of the Iron Metabolism Index / 中国医学科学院学报

Objective To establish a mouse model of exogenous iron overload combined with tuberculosis(TB). Methods C57BL/6N mice were divided into negative control, low-, medium-, and high-dose iron groups and received intraperitoneal injection of iron dextran at 0, 3.75, 7.50, and 15.00 mg/dose(3 times/week for 4 weeks), respectively.After 4 weeks, the organ morphology and body weight of the mice were evaluated.The content of serum iron, ferritin, transferrin, and transferrin receptor was determined by ELISA.Heart, liver, spleen, lung, kidney, and small intestine were analyzed for tissue iron content and iron deposition pathology.

Proliferation kinetics of immune cells during early phase of bone marrow transplantation in mouse model based on chemotherapy conditioning / 中南大学学报(医学版)

OBJECTIVES@#To establish mouse bone marrow transplantation by pretreatment with chemotherapy, and to explore the dynamic changes of immune cells in the early stage of allogeneic transplantation in the spleen of mice.@*METHODS@#Mice were divided into 4 groups (80 mg/kg group, 100 mg/kg group, 120 mg/kg group, and 150 mg/kg group) according to the difference in dose of busulfan. The mice were treated with busulfan and cyclophosphamide combined chemotherapy, and the appropriate dosage was determined by evaluating the myeloablative effect and drug toxicity. According to the type of the genetic transplantation, the mice were also divided into 4 groups: An allogeneic transplantation group, a homogenic transplantation group, a chemotherapy alone group, and a normal control group. The mice were pretreated with busulfan and cyclophosphamide before bone marrow transplantation. In the allogeneic transplantation group, the suspension of splenocytes was prepared at the first day, the 3rd day, the 5th day, and the 8th day after transplantation for flow cytometry detection, and the dynamic changes of splenic immune cells were analyzed. The homogeneic transplantation group served as the concurrent control, the normal control group served as the control of basic value of spleen immune cells, and the chemotherapy alone group was used to evaluate the myeloablative effect.@*RESULTS@#1) The optimal dose of busulfan was 100 mg/kg. The combination of busulfan and cyclophosphamide can restore the hematopoiesis of transplanted mice, and the toxicity associated with pretreatment is small. 2) In the allogeneic transplantation group: The hematopoietic reconstitution and high donor chimerism rate were achieved after transplantation. In the early phase of bone marrow transplantation, the T lymphocytes were the main cell group, while the recovery of B lymphocytes was relatively delayed. The dendritic cells and natural killer cells from donors were the earliest cells to recover and achieve high chimerism rate compared with T cells and B cells. Most T cells were in the initial T cell state within 5 days after allogeneic transplantation. However, in the 5th day after transplantation, these cells were mainly in the effective memory phenotype. The reconstruction of donor-derived naive T cells was slow, but the reconstruction of donor-derived effective memory T cells and regulatory T cells was relatively fast. 3) In the homogeneic transplantation group: The mice could recover hematopoiesis and the recovery of B lymphocytes was delayed. 4) In the chemotherapy alone group: All mice died in 12-15 days after chemotherapy, and the peripheral blood routine showed pancytopenia before death.@*CONCLUSIONS@#Pretreatment with chemotherapy can successfully establish the mouse model of bone marrow transplantation. There are difference in the proportion of T cells, B cells, natural killer cells, dendritic cells, effector memory T cells, initial T cells, and regulatory T cells after transplantation, and the relationship between donor and recipient is also changed.

The study of the mechanism related to abdominal aortic aneurysm formation in elastase-induced aneurysm mice model / 中华胸心血管外科杂志

Objective:To establish a mouse model of the abdominal aortic aneurysm by elastase perfusion and to provide a reference for the study of the mechanism related to abdominal aortic aneurysm formation.Methods:AAAs were induced by porcine pancreatic elastase (PPE) infusion in male C57BL/6 mice. The control group was perfused with normal saline (Saline). The changes in abdominal aortic diameter were compared at 14 days after perfusion. The diameter of the abdominal aorta stained with HE was measured. The destruction of the elastic plate in the abdominal aortic wall was observed by elastic plate staining. TUNEL assay was used to evaluate the apoptosis in aneurysm tissues.Results:Porcine pancreatic elastase (PPE) perfusion successfully established the mouse model of abdominal aortic aneurysm, in which an aneurysm formation rate was 100% at 14 days after the operation. After modelling, the abdominal aorta diameter in the mouse was significantly increased, higher than that in the control group perfused with normal saline ( P<0.05). In the PPE group, the elastic plate of the aortic wall was straightened and thinned, and interrupted. The proportion of TUNEL-positive cells in the PPE group was significantly higher than that in the control group perfused with normal saline ( P<0.05). Conclusion:Elastase perfusion can stably establish the abdominal aortic aneurysm model, and we observe the destruction of the elastic plate in the medial layer of the abdominal aortic wall and the up-regulation of the apoptosis process in the model. It provides a reference to study the pathogenesis of abdominal aortic aneurysm further.