Impact of lithocholic acid on the osteogenic and adipogenic differentiation balance of bone marrow mesenchymal stem cells / 中国修复重建外科杂志

OBJECTIVE@#To Investigate the effects of lithocholic acid (LCA) on the balance between osteogenic and adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs).@*METHODS@#Twelve 10-week-old SPF C57BL/6J female mice were randomly divided into an experimental group (undergoing bilateral ovariectomy) and a control group (only removing the same volume of adipose tissue around the ovaries), with 6 mice in each group. The body mass was measured every week after operation. After 4 weeks post-surgery, the weight of mouse uterus was measured, femur specimens of the mice were taken for micro-CT scanning and three-dimensional reconstruction to analyze changes in bone mass. Tibia specimens were taken for HE staining to calculate the number and area of bone marrow adipocytes in the marrow cavity area. ELISA was used to detect the expression of bone turnover markers in the serum. Liver samples were subjected to real-time fluorescence quantitative PCR (RT-qPCR) to detect the expression of key genes related to bile acid metabolism, including cyp7a1, cyp7b1, cyp8b1, and cyp27a1. BMSCs were isolated by centrifugation from 2 C57BL/6J female mice (10-week-old). The third-generation cells were exposed to 0, 1, 10, and 100 μmol/L LCA, following which cell viability was evaluated using the cell counting kit 8 assay. Subsequently, alkaline phosphatase (ALP) staining and oil red O staining were conducted after 7 days of osteogenic and adipogenic induction. RT-qPCR was employed to analyze the expressions of osteogenic-related genes, namely ALP, Runt-related transcription factor 2 (Runx2), and osteocalcin (OCN), as well as adipogenic-related genes including Adiponectin (Adipoq), fatty acid binding protein 4 (FABP4), and peroxisome proliferator-activated receptor γ (PPARγ).@*RESULTS@#Compared with the control group, the body mass of the mice in the experimental group increased, the uterus atrophied, the bone mass decreased, the bone marrow fat expanded, and the bone metabolism showed a high bone turnover state. RT-qPCR showed that the expressions of cyp7a1, cyp8b1, and cyp27a1, which were related to the key enzymes of bile acid metabolism in the liver, decreased significantly ( P<0.05), while the expression of cyp7b1 had no significant difference ( P>0.05). Intervention with LCA at concentrations of 1, 10, and 100 μmol/L did not demonstrate any apparent toxic effects on BMSCs. Furthermore, LCA inhibited the expressions of osteogenic-related genes (ALP, Runx2, and OCN) in a dose-dependent manner, resulting in a reduction in ALP staining positive area. Concurrently, LCA promoted the expressions of adipogenic-related genes (Adipoq, FABP4, and PPARγ), and an increase in oil red O staining positive area.@*CONCLUSION@#After menopause, the metabolism of bile acids is altered, and secondary bile acid LCA interferes with the balance of osteogenic and adipogenic differentiation of BMSCs, thereby affecting bone remodelling.

Panax notoginseng saponin relieving the inflammatory pain caused by complete Freund’s adjuvant by inhibiting the activation of astrocytes in mice / 解剖学报

Objective To analyse the analgesic effect and possible mechanism of panax notoginseng saponin (PNS) on mouse models of chronic inflammatory pain caused by complete Freund’s adjuvant (CFA). Methods A total of 48 male C57BL/ 6J mice were divided randomly into four groups: normal saline control group (Ctrl), CFA group (CFA), CFA + PNS group (CFA+PNS), CFA + dexamethasone (DEX) group (CFA+DEX). Von Frey filaments were used to detect mechanical pain in mice. Immunohistochemistry was used to detect the number and morphological changes of glial fibrillary acidic protein (GFAP) positive astrocytes. Western blotting was used to detect the expressions of GFAP, nucleotide-binding and oligomerization domain(NOD)-like receptor thermal protein domain associated protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), Caspase-1, interleukin (IL)-1β, and IL-18 in mice’s spinal cord segments in each group. Results Compared with the Ctrl group, mice in the CFA group showed a significant decrease in mechanical pain thresholds at day 1, day 3, day 5, day 7, and day 14. Additionally, there was a significant decrease in NLRP3, ASC, Caspase-1, IL-1β and IL-18 in the spinal cord of the mice. PNS intervention could relieve mechanical pain and down-regulate the expressions of NLRP3, ASC, Caspase-1, IL-1β and IL-18 in the spinal cord of mice, with no significant difference compared with the CFA+DEX group. CFA group mice had significantly more GFAP positive cells in their posterior horns than Ctrl group mice, as measured by immunohistochemistry; PNS intervention decreased the number of GFAP positive cells in the posterior horn of the spinal cord in model mice;DEX had no effect on the number of GFAP positive cells in the dorsal horn of spinal cord. According to Western blotting results, GFAP expression in the spinal cord of the CFA group was significantly more than that of the Ctrl group; PNS intervention significantly reduced GFAP expression in the spinal cord of CFA group mice;DEX had no effect on the expression of GFAP in the posterior horn of spinal cord. Conclusion PNS has a good alleviating effect on inflammatory pain, and its mechanism may be related to inhibition of astrocyte activation and NLRP3 inflammasome activation.

Research on the dynamic changes of neurological dysfunction and cognitive function impairment in traumatic brain injury / 解剖学报

Objective To explore the dynamic changes and mechanisms of neurological and cognitive functions in mice with traumatic brain injury (TBI). Methods Totally 60 12⁃month⁃old Balb/ c mice were divided into control group (10 in group) and TBI group (50 in group). TBT model mice were divided into 5 subgroups according to the time of model construction, including model 1 day, model 1 day, model 3 day, model 7 day, model 14 days and model 28 days group with 10 in each group. At the 29th day of the experiment, neurological scores and step down tests were carried out. After the test, the mice were sacrificed for brains which were detected by immunohistochemistry staining, inflammatory cytokine tests and Western blotting. Results Compared with the control group, the neurological scores of mice in TBI group increased, and then decreased after the 7th day when the scores reached the peak. However, the latency of step down errors was lower than control group, and the number of step down errors was higher than control group which had no changes. Compared with the control group, the expression of lonized calcium⁃binding adapter molecule 1(IBA1), chemokine C⁃X3⁃C⁃motif ligand1 (CX3CL1), C⁃X3⁃C chemokine receptor 1(CX3CR1), NOD⁃like receptor thermal protein domain associated protein 3 (NLRP3), and phosphorylation nuclear factor(p⁃NF)⁃κB in TBI group increased and reached to the peak at the 7th day, and then started to decrease. At the same time, the levels of inflammatory cytokines interleukin⁃6(IL⁃6) and tumor necrosis factor⁃α(TNF⁃α) first increased to the peak, and then began to decrease. However, compared with the control group, the expression of amyloid β(Aβ) protein and p⁃Tau protein in the model group continued to increase at all time. Conclusion The TBI model caused continuous activation of microglia along with inflammatory response, which first increased and then decreased, resultsing in neurological scores changes. In addition, the inflammatory response may act as a promoter of Aβ protein deposition and Tau protein phosphorylation, leading to cognitive impairment in mice.

Role of inhibiting lncRNA TUG1 to down⁃regulate nucleotide binding oligomerization domain like receptor protein 1 inflammasome in delaying the progression of Alzheimer’s disease / 解剖学报

Objective To investigate the relieving effects of knockdown of long non-coding RNA(lncRNA)taurine up-regulated gene 1 (TUG1) on inhibiting nucleotide binding oligomerization domain like receptor protein 1 (NLRP1) inflammasome and the progression of Alzheimer’ s disease. Methods Wild-type (WT group, 10 mice) or amyloid precursor protein (APP) / presenilin-1 (PS1) transgenic mice (30 mice) with a genetic background of C57 / BL6 aged 9-10 weeks were used in this study. APP / PS1 transgenic mice were randomly divided into model group, model+lncRNA TUG1 short hairpin RNA (shRNA) group and model + shRNA non target (NT) group (n = 10) . Blood samples, cerebral cortex tissues, primary microglial cells and primary astrocytes were collected from mice 12 weeks of age on day 1 (3-month-old) and 32 weeks of age on day 1 (8-month-old), with 5 mice per group at each time point. Real-time PCR analysis was used to detect the expression levels of lncRNA TUG1 and macrophage migration inhibitory factor (MIF) mRNA in cerebral cortex tissues and primary microglial cells, and C1r and C1s mRNA levels in primary astrocytes of 3-month-old and 8-month-old mice in the above 4 groups, respectively. ELISA was used to determine the MIF in plasma samples of the above 4 groups of mice. Primary microglia and astrocytes from the cerebral cortex of 3-month-old and 8-month-old mice were co-cultured. CCK-8 method was used to determine the proliferation ability of the above cells. Western blotting was used to determine the expression levels of MIF, pro interleukin-1β (pro-IL-1β), apoptosis associated speck-like protein containing a caspase recrult domain(ASC), Caspase-1 (p20), Caspase-1 (full), NLRP1 and NLRP3 in cerebral cortex tissues of 3-month-old and 8-month-old mice. Immunofluorescent staining was used to determine amyloid beta(Aβ) in cerebral cortex of 8-month-old mice. Results At the age of 3-month-old and 8-month-old, compared with the WT group, the relative expression level of lncRNA TUG1 and MIF in cerebral cortex tissues and primary microglia of model group mice was significantly up-regulated, with primary microglial cells and astrocytes proliferation ability enhanced (P0. 05) . There was no significant difference between the model group and the model+shRNA NT group mice of all the above factors (P>0. 05) . Conclusion In APP / PS1 transgenic mice, up-regulation of lncRNA TUG1 and MIF are positively associated with the activation of NLRP1 inflammasome in mice cerebral cortex tissues and primary microglia. Knock-down of lncRNA TUG1 can ameliorate the progression of Alzheimer’ s disease.

Nuclear factor-KB signaling pathway and gender differences in alcoholic liver fibrosis / 解剖学报

Objective To investigate the relationship between nuclear factor(NF)-κB signaling pathway and gender differences in alcoholic liver fibrosis. Methods C57BL/6 N mice at 7-8 weeks of age were randomly divided into: male normal group, male model group, female normal group and female model group of 20 mice each. The normal group was fed with control liquid diet for 8 weeks, and the model group was fed with alcoholic liquid diet for 8 weeks combined with 31.5% ethanol gavage (5g/kg twice a week) to establish an alcoholic liver fibrosis model. The mice were executed at the end of 8 weekends, and the alanine aminotransferase (ALT), aspartate aminotransferase (AST) activity, estradiol (E

Research progress on bone metabolism and molecular mechanisms in accelerated aging SAMP6 mice / 中国药理学通报

Senile osteoporosis (SOP) is a systemic bone disease characterized by increased susceptibility to fractures. The pathogenesis of SOP is complex and not well understood. Currently, the rapid aging model mouse, senescence accelerated mouse prone 6 (SAMP6), is an ideal model for studying the mechanisms of SOP development and exploring its prevention and treatment. This model exhibits characteristics including increased bone fragility, degradation of bone microstructure, loss of bone matrix, and abnormal metabolism and dysfunction of bone cells, faithfully replicating the process of SOP occurrence and progression at both macroscopic and microscopic levels.

Effect of LAG3 deficiency on natural killer cell function and hepatic fibrosis in mice infected with Echinococcus multilocularis / 中国血吸虫病防治杂志

Objective To investigate the effect of LAG-3 deficiency (LAG3-/-) on natural killer (NK) cell function and hepatic fibrosis in mice infected with Echinococcus multilocularis. Methods C57BL/6 mice, each weighing (20 ± 2) g, were divided into the LAG3-/- and wild type (WT) groups, and each mouse in both groups was inoculated with 3 000 E. multilocularis protoscoleces via the hepatic portal vein. Mouse liver and spleen specimens were collected 12 weeks post-infection, sectioned and stained with sirius red, and the hepatic lesions and fibrosis were observed. Mouse hepatic and splenic lymphocytes were isolated, and flow cytometry was performed to detect the proportions of hepatic and splenic NK cells, the expression of CD44, CD25 and CD69 molecules on NK cell surface, and the secretion of interferon γ (IFN-γ), tumor necrosis factor α (TNF-α), interleukin (IL)-4, IL-10 and IL-17A. Results Sirius red staining showed widening of inflammatory cell bands and hyperplasia of fibrotic connective tissues around mouse hepatic lesions, as well as increased deposition of collagen fibers in the LAG3-/-group relative to the WT group. Flow cytometry revealed lower proportions of mouse hepatic (6.29% ± 1.06% vs. 11.91% ± 1.85%, P < 0.000 1) and splenic NK cells (4.44% ± 1.22% vs. 5.85% ± 1.10%, P > 0.05) in the LAG3-/- group than in the WT group, and the mean fluorescence intensity of CD44 was higher on the surface of mouse hepatic NK cells in the LAG3-/- group than in the WT group (t = −3.234, P < 0.01), while no significant differences were found in the mean fluorescence intensity of CD25 or CD69 on the surface of mouse hepaticNK cells between the LAG3-/- and WT groups (both P values > 0.05). There were significant differences between the LAG3-/- and WT groups in terms of the percentages of IFN-γ (t = −0.723, P > 0.05), TNF-α (t = −0.659, P > 0.05), IL-4 (t = −0.263, P > 0.05), IL-10 (t = −0.455, P > 0.05) or IL-17A secreted by mouse hepatic NK cells (t = 0.091, P > 0.05), and the percentage of IFN-γ secreted by mouse splenic NK cells was higher in the LAG3-/- group than in the WT group (58.40% ± 1.64% vs. 50.40% ± 4.13%; t = −4.042, P < 0.01); however, there were no significant differences between the two groups in terms of the proportions of TNF-α (t = −1.902, P > 0.05), IL-4 (t = −1.333, P > 0.05), IL-10 (t = −1.356, P > 0.05) or IL-17A secreted by mouse splenic NK cells (t = 0.529, P > 0.05). Conclusions During the course of E. multilocularis infections, LAG3-/- promotes high-level secretion of IFN-γ by splenic NK cells, which may participate in the reversal the immune function of NK cells, resulting in aggravation of hepatic fibrosis.

Isolation and identification of exosomes from mouse primary peritoneal macrophages / 中国生物制品学杂志

@#Objective To isolate,purify and identify exosomes secreted by mouse primary peritoneal macrophages.Methods Five male C57BL/6 mice were intraperitoneally injected with 3% mercaptoacetate broth respectively,and the primary peritoneal macrophages were obtained by lavage,and then the purity was analyzed by flow cytometry.The exosomes of mouse primary peritoneal macrophages were extracted by ExoQuick TC exosome kit,which were measured for the protein content with BCA kit,observed for the morphology by transmission electron microscopy,detected for the particle size and distribution with nanoparticle tracking analyzer,and determined for the expression of exosome-specific markers(CD9,CD63 and TSG101) by Western blot.Results About 5 × 10~6 peritoneal macrophages with the purity of(99.17±0.65)%were obtained from each mouse.Approximately 869 μg of exosomal protein was extracted from 5 mL of mouse primary peritoneal macrophage culture supernatant.The exosomes of mouse primary peritoneal macrophages were typical tea saucerlike vesicles with strong refraction under electron microscopy,and highly expressed the exosome-specific markers TSG101,CD63 and CD9.The particle size distribution was concentrated between 100 and 200 nm,with an average particle size of175.2 nm.Conclusion Intraperitoneal injection of mercaptoacetate broth can improve the yield of mouse primary peritoneal macrophages.ExoQuick TC.exosome kit can extract sufficient amount of exosomes with high purity from mouse primary peritoneal macrophages.

Mechanism of Astragaloside Ⅳ on db/db Mice with Type 2 Diabetes Mellitus and Non-alcoholic Fatty Liver Disease Based on AMPK Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo study the mechanism of astragaloside Ⅳ （AS Ⅳ） on db/db mice with type 2 diabetes mellitus （T2DM） and non-alcoholic fatty liver disease （NAFLD） based on network pharmacology and experimental validation. MethodA total of 24 db/db mice were randomly divided into four groups： model group， metformin group， and low-dose and high-dose AS Ⅳ groups. Six C57 mice were used as the blank group. The low-dose and high-dose AS Ⅳ groups were given AS Ⅳ of 0.015 and 0.030 g·kg-1 by gavage， and the metformin group was given 0.067 g·kg-1 by gavage. The blank and model groups were given equal volumes of distilled water by gavage. After intragastric administration， fasting blood glucose （FBG） was detected， and an oral glucose tolerance test was performed. Serum lipid level and liver histopathology were detected. The target and enrichment pathway of AS Ⅳ for treating T2DM and NAFLD were predicted by network pharmacology， and the main enrichment pathway was verified by molecular biology techniques. The protein expressions of AMPK， p-AMPK， sterol regulatory element-binding protein-1 （SREBP-1）， and fatty acid synthetase （FAS） in liver tissue were detected by Western blot. ResultCompared with the blank group， the levels of body mass， liver weight coefficient， fasting blood glucose， serum total cholesterol， triglyceride， and low-density lipoprotein cholesterol in mice treated with AS Ⅳ were decreased （P<0.05， P<0.01）. The pathology of liver tissue showed significant improvement in lipid accumulation， and imaging results showed that the degree of fatty liver was reduced after AS Ⅳ therapy. Network pharmacological prediction results showed that vascular endothelial growth factor α （VEGFA）， galactoagglutinin 3 （LGALS3）， serine/threonine kinase B2 （Akt2）， RHO-associated coiled-coil protein kinase 1 （ROCK1）， serine/threonine kinase B1 （Akt1）， signaling and transcriptional activator protein （STAT3）， and messtimal epidermal transformation factor （MET） were key targets in "drug-disease" network. The results from the Kyoto encyclopedia of genes and genomes （KEGG） enrichment showed that the AMP-dependent protein kinase （AMPK） signaling pathway was strongly associated with T2DM and NAFLD. Western blot results showed that compared with the blank group， the expression levels of p-AMPK/AMPK in the model group were significantly down-regulated， while those of SREBP-1 and FAS proteins were significantly up-regulated （P<0.01）. Compared with the model group， the expression levels of p-AMPK/AMPK in the metformin group and high-dose AS Ⅳ group were significantly up-regulated， while those of SREBP-1 and FAS proteins were significantly down-regulated （P<0.05， P<0.01）. ConclusionAS Ⅳ regulates the expression of lipid proteins by activating the AMPK signaling pathway， thereby improving lipid metabolism.

FVB/NJ strain as a mouse model for cutaneous leishmaniasis by Leishmania (L.) amazonensis

BACKGROUND Leishmaniases encompass a spectrum of neglected diseases caused by parasites of the genus Leishmania, grouped in two forms: tegumentary and visceral leishmaniasis. OBJECTIVES In this study, we propose Friend Virus B NIH Jackson (FVB/NJ) mouse strain as a new experimental model of infection with Leishmania (Leishmania) amazonensis, the second most prevalent agent of tegumentary leishmaniasis in Brazil. METHODS AND FINDINGS We performed in vitro infections of FVB/NJ macrophages and compared them with BALB/c macrophages, showing that BALB/c cells have higher infection percentages and a higher number of amastigotes/cell. Phagocytosis assays indicated that BALB/c and FVB/NJ macrophages have similar capacity to uptake parasites after 5 min incubations. We also investigated promastigotes' resistance to sera from FVB/NJ and BALB/c and observed no difference between the two sera, even though FVB/NJ has a deficiency in complement components. Finally, we subcutaneously infected FVB/NJ and BALB/c mice with 2 × 106 parasites expressing luciferase. Analysis of lesion development for 12 weeks showed that FVB/NJ and BALB/c mice have similar lesion profiles and parasite burdens. MAIN CONCLUSIONS This work characterises for the first time the FVB/NJ mouse as a new model for tegumentary leishmaniasis caused by Leishmania (L.) amazonensis.

Efecto de Tropaeolum Tuberosum o "Mashua" (tropaeolaceae) sobre la expresión génica relacionada a espermatogénesis en ratón

Introducción: Tropaeolum tuberosum, conocido comomashua, es un tubérculo andino que tiene un valor tanto económico como nutritivo para las poblaciones de pocos recursos. Se cree que afecta la fertilidad masculina, porque los hombres andinos lo relacionan con impotencia y disminución de la capacidad fecundante. Estudios hechos en ratas que se alimentaron con mashua demostraron que hubo un 45% de decrecimiento de la tasa testosterona/dihidrotestosterona. El efecto de esta planta en la reproducción está relacionada a su contenido de isotiocianatos, compuestos que se unen covalentemente a las proteínas, las cuales pueden estar directa o indirectamente involucradas en el proceso espermatogénico. El propósito de esta investigación fue evaluar el efecto del extracto acuoso de la mashua sobre la espermatogénesis y la fisiología reproductiva de ratones. Métodos: Se evaluaron los parámetros morfofuncionales in vivo de espermios de ratones (espermatograma) y se cuantificó la expresión de: Cytochrome P450 17α-hydroxylase/17,20-lyase, proteína reguladora de esteroidogénesis aguda, ciclina y protamina, relacionados a la espermatogénesis. Resultados: A los 7, 14 y 21 días de dosificación, se vio afectado el conteo de espermatozoides, así como su motilidad progresiva (MP); por otra parte, se observó un retardo en la maduración de los mismos. En cuanto a la expresión génica, no se encontró diferencias significativas entre la expresión de los dos genes estudiados (cytochrome P450 17α-hydroxylase/17,20-lyase, ciclina). Conclusión: El efecto de la mashua no se da a nivel de la expresión de los genes involucrados en la espermatogénesis, sino a nivel de sus funciones como proteína.

Introduction: Tropaeolum tuberosum, known as "mashua" is an Andean tuber that holds both economic and nutritional value for low-income populations. It is believed that it affects male fertility because Andean men associate it with impotence and decreased fertility. Studies conducted on rats fed with "mashua" showed that there was a 45% decrease in the testosterone/dihydrotestosterone ratio. The effect of this plant on reproduction is related to its content of isothiocyanates, compounds that covalently bind to proteins, which may be directly or indirectly involved in the spermatogenic process. The purpose of this research was to evaluate the effect of the aqueous extract of "mashua" on spermatogenesis and reproductive physiology of mice. Methods: In vivo morphofunctional parameters of mouse sperm (spermatogram) were evaluated and the expression of Cytochrome P450 17α-hydroxylase/17,20-lyase, acute steroidogenesis regulatory protein, cyclin, and protamine related to spermatogenesis was quantified. Results: The results indicated that at 7, 14 and 21 days of dosing, the sperm count was affected, as well as their progressive motility (PM), on the other hand, a delay in their maturation was observed. Regarding gene expression, no significant differences were found between the expression of the two genes studied (Cytochrome P450 17α-hydroxylase/17,20-lyase, Cyclin). Conclusion: The effect of "mashua" does not occur at the level of gene expression involved in spermatogenesis, but at the level of its functions as a protein.

Phytochemical evaluation and anti-psoriatic activity of the ethanolic extract of the leaves of Thespesia populnea

Psoriasis is a chronic, mild and common inflammatory skin condition. Still an ideal treatment for psoriasis, effective, safe, convenient, and economical is not available. In this scenario, the search for suitable alternative treatments with minimal side effects is necessary. Plants can be effective and alternative in this regard. Therefore, this article discusses the leaves of the plants Thespesia populnea (Malvaceae) that are traditionally used in the treatment of psoriasis. The present study aimed to assess anti-psoriatic activity. The dried leaves of the plants were subjected to soxhlation with 95% ethanol and phytochemical studies were performed. The anti-psoriatic activity was evaluated by the Mouse-Tail model. It is a relatively sensitive and reproducible morphometric method that allows quantitative evaluation of the effects of anti-psoriatics through epidermal differentiation. Extracts were applied topically at a dose of 500mg/kg over 14 days and at the end, the animals were sacrificed, longitudinal histological sections were made of the tail skin and the degree of orthokeratosis was determined. It was significantly (P <0.05) increased by the ethanolic extract of Thespesia populnea (52.86±2.86) compared to the control (17.30±4.09). In relative epidermal thickness, the ethanolic extract of Thespesia populnea (92.68±8.8) showed a significant difference (P <0.05) compared to the control (100±10.7). The data obtained suggest that the selected plant has anti-psoriatic activity and confirms its traditional use in the treatment of psoriasis.

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.

Role and mechanisms of CHI3L1 in coronary artery lesions in a mouse model of Kawasaki disease-like vasculitis / 中国当代儿科杂志

OBJECTIVES@#To explore the role and potential mechanisms of chitinase-3-like protein 1 (CHI3L1) in coronary artery lesions in a mouse model of Kawasaki disease (KD)-like vasculitis.@*METHODS@#Four-week-old male SPF-grade C57BL/6 mice were randomly divided into a control group and a model group, with 10 mice in each group. The model group mice were intraperitoneally injected with 0.5 mL of lactobacillus casei cell wall extract (LCWE) to establish a mouse model of KD-like vasculitis, while the control group mice were injected with an equal volume of normal saline. The general conditions of the mice were observed on the 3rd, 7th, and 14th day after injection. Changes in coronary artery tissue pathology were observed using hematoxylin-eosin staining. The level of CHI3L1 in mouse serum was measured by enzyme-linked immunosorbent assay. Immunofluorescence staining was used to detect the expression and localization of CHI3L1, von Willebrand factor (vWF), and α-smooth muscle actin (α-SMA) in coronary artery tissue. Western blot analysis was used to detect the expression of CHI3L1, vWF, vascular endothelial cadherin (VE cadherin), Caspase-3, B cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax), nuclear factor κB (NF-κB), and phosphorylated NF-κB (p-NF-κB) in coronary artery tissue.@*RESULTS@#The serum level of CHI3L1 in the model group was significantly higher than that in the control group (P<0.05). Compared to the control group, the expression of CHI3L1 in the coronary artery tissue was higher, while the expression of vWF was lower in the model group. The relative expression levels of CHI3L1, Bax, Caspase-3, NF-κB, and p-NF-κB were significantly higher in the model group than in the control group (P<0.05). The relative expression levels of vWF, VE cadherin, and Bcl-2 were lower in the model group than in the control group (P<0.05).@*CONCLUSIONS@#In the LCWE-induced mouse model of KD-like vasculitis, the expression levels of CHI3L1 in serum and coronary arteries increase, and it may play a role in coronary artery lesions through endothelial cell apoptosis mediated by inflammatory reactions.

Mechanism of miR-26a-5p/cAMP response element binding protein 1 molecular axis regulating osteogenic differentiation of adipose-derived mesenchymal stem cells / 中国修复重建外科杂志

OBJECTIVE@#To investigate the regulatory effects of miR-26a-5p on the osteogenic differentiation of adipose-derived mesenchymal stem cells (ADSCs) by regulating cAMP response element binding protein 1 (CREB1).@*METHODS@#The adipose tissues of four 3-4 weeks old female C57BL/6 mice were collected and the cells were isolated and cultured by digestion separation method. After morphological observation and identification by flow cytometry, the 3rd-generation cells were subjected to osteogenic differentiation induction. At 0, 3, 7, and 14 days after osteogenic differentiation induction, the calcium deposition was observed by alizarin red staining, ALP activity was detected, miR- 26a-5p and CREB1 mRNA expressions were examined by real-time fluorescence quantitative PCR, and CREB1 protein and its phosphorylation (phospho-CREB1, p-CREB1) level were measured by Western blot. After the binding sites between miR-26a-5p and CREB1 was predicted by the starBase database, HEK-293T cells were used to conduct a dual-luciferase reporter gene experiment to verify the targeting relationship (represented as luciferase activity after 48 hours of culture). Finally, miR-26a-p inhibitor (experimental group) and the corresponding negative control (control group) were transfected into ADSCs. Alizarin red staining, ALP activity, real-time fluorescent quantitative PCR (miR-26a-5p) and Western blot [CREB1, p-CREB1, Runt-related transcription factor 2 (RUNX2), and osteocalcin (OCN)] were performed at 7 and 14 days after osteogenic induction culture.@*RESULTS@#The cultured cells were identified as ADSCs. With the prolongation of osteogenic induction culture, the number of calcified nodules and ALP activity significantly increased ( P<0.05). The relative expression of miR-26a-5p in the cells gradually decreased, while the relative expressions of CREB1 mRNA and protein, as well as the relative expression of p-CREB1 protein were increased. The differences were significant between 7, 14 days and 0 day ( P<0.05). There was no significant difference in p-CREB1/CREB1 between different time points ( P>0.05). The starBase database predicted that miR-26a-5p and CREB1 had targeted binding sequences, and the dual-luciferase reporter gene experiment revealed that overexpression of miR-26a-5p significantly suppressed CREB1 wild-type luciferase activity ( P<0.05). After 7 and 14 days of osteogenic induction, compared with the control group, the number of calcified nodules, ALP activity, and relative expressions of CREB1, p-CREB1, OCN, and RUNX2 proteins in the experimental group significantly increased ( P<0.05). There was no significant difference in p-CREB1/CREB1 between the two groups ( P>0.05).@*CONCLUSION@#Knocking down miR-26a-5p promoted the osteogenic differentiation of ADSCs by up-regulating CREB1 and its phosphorylation.

Advances in Modeling of Multiple Myeloma in Mice / 中国医学科学院学报

Multiple myeloma(MM)is a systemic malignancy of plasma cells.Nowadays,the basic research on MM is flourishing with the continuous optimization and innovation of mouse models of MM.Heterologous mouse models of MM established with human-derived cells and immunodeficient mice have been applied in assessing drug efficacy,exploring drug resistance mechanisms,and observing tumor-bone marrow microenvironment interactions.In the last decades,the homologous mouse models of MM established with murine-derived cells or gene-editing technologies have been widely used in the research on the pathogenesis and drug development.Additionally,the stable modeling of targeted organ injury will be a key problem to be tackled in this field.This review summarizes the characteristics and application progress of mouse models of MM.

Generation of Mlk3 KO mice by CRISPR/Cas9 and its effect on blood pressure / 生物工程学报

To explore the effect of Mlk3 (mixed lineage kinase 3) deficiency on blood pressure, Mlk3 gene knockout (Mlk3KO) mice were generated. Activities of sgRNAs targeted Mlk3 gene were evaluated by T7 endonuclease I (T7E1) assay. CRISPR/Cas9 mRNA and sgRNA were obtained by in vitro transcription, microinjected into zygote, followed by transferring into a foster mother. Genotyping and DNA sequencing confirmed the deletion of Mlk3 gene. Real- time PCR (RT-PCR), Western blotting or immunofluorescence analysis showed that Mlk3KO mice had an undetectable expression of Mlk3 mRNA or Mlk3 protein. Mlk3KO mice exhibited an elevated systolic blood pressure compared with wild-type mice as measured by tail-cuff system. Immunohistochemistry and Western blotting analysis showed that the phosphorylation of MLC (myosin light chain) was significantly increased in aorta isolated from Mlk3KO mice. Together, Mlk3KO mice was successfully generated by CRISPR/Cas9 system. MLK3 functions in maintaining blood pressure homeostasis by regulating MLC phosphorylation. This study provides an animal model for exploring the mechanism by which Mlk3 protects against the development of hypertension and hypertensive cardiovascular remodeling.

Tumor cell lysate with low content of HMGB1 enhances immune response of dendritic cells against lung cancer in mice / 南方医科大学学报

OBJECTIVE@#To assess the effect of tumor cell lysate (TCL) with low high-mobility group B1 (HMGB1) content for enhancing immune responses of dendritic cells (DCs) against lung cancer.@*METHODS@#TCLs with low HMGB1 content (LH-TCL) and normal HMGB1 content (NH-TCL) were prepared using Lewis lung cancer (LLC) cells in which HMGB1 was inhibited with 30 nmol/L glycyrrhizic acid (GA) and using LLC cells without GA treatment, respectively. Cultured mouse DCs were exposed to different doses of NH-TCL and LH-TCL, using PBS as the control. Flow cytometry was used to detect the expressions of CD11b, CD11c and CD86 and apoptosis of the stimulated DCs, and IL-12 levels in the cell cultures were detected by ELISA. Mouse spleen cells were co-cultured with the stimulated DCs, and the activation of the spleen cells was assessed by detecting CD69 expression using flow cytometry; TNF-β production in the spleen cells was detected with ELISA. The spleen cells were then co-cultured with LLC cells at the effector: target ratios of 5:1, 10:1 and 20:1 to observe the tumor cell killing. In the animal experiment, C57/BL6 mouse models bearing subcutaneous LLC xenograft received multiple injections with the stimulated DCs, and the tumor growth was observed.@*RESULTS@#The content of HMGB1 in the TCL prepared using GA-treated LLC cells was significantly reduced (P < 0.01). Compared with NH-TCL, LH-TCL showed a stronger ability to reduce apoptosis (P < 0.001) and promote activation and IL- 12 production in the DCs. Compared with those with NH-TCL stimulation, the DCs stimulated with LH-TCL more effectively induced activation of splenic lymphocytes and enhanced their anti-tumor immunity (P < 0.05). In the cell co-cultures, the spleen lymphocytes activated by LH-TCL-stimulated DCs showed significantly enhanced LLC cell killing activity (P < 0.01). In the tumor-bearing mice, injections of LH-TCL-stimulated DCs effectively activated host anti-tumor immunity and inhibited the growth of the tumor xenografts (P < 0.05).@*CONCLUSION@#Stimulation of the DCs with LH-TCL enhances the anti-tumor immune activity of the DCs and improve the efficacy of DCbased immunotherapy for LLC in mice.

Single-cell transcriptomic atlas of mouse cochlear aging

Progressive functional deterioration in the cochlea is associated with age-related hearing loss (ARHL). However, the cellular and molecular basis underlying cochlear aging remains largely unknown. Here, we established a dynamic single-cell transcriptomic landscape of mouse cochlear aging, in which we characterized aging-associated transcriptomic changes in 27 different cochlear cell types across five different time points. Overall, our analysis pinpoints loss of proteostasis and elevated apoptosis as the hallmark features of cochlear aging, highlights unexpected age-related transcriptional fluctuations in intermediate cells localized in the stria vascularis (SV) and demonstrates that upregulation of endoplasmic reticulum (ER) chaperon protein HSP90AA1 mitigates ER stress-induced damages associated with aging. Our work suggests that targeting unfolded protein response pathways may help alleviate aging-related SV atrophy and hence delay the progression of ARHL.

Noninvasive Tracking of Every Individual in Unmarked Mouse Groups Using Multi-Camera Fusion and Deep Learning / 神经科学通报·英文版

Accurate and efficient methods for identifying and tracking each animal in a group are needed to study complex behaviors and social interactions. Traditional tracking methods (e.g., marking each animal with dye or surgically implanting microchips) can be invasive and may have an impact on the social behavior being measured. To overcome these shortcomings, video-based methods for tracking unmarked animals, such as fruit flies and zebrafish, have been developed. However, tracking individual mice in a group remains a challenging problem because of their flexible body and complicated interaction patterns. In this study, we report the development of a multi-object tracker for mice that uses the Faster region-based convolutional neural network (R-CNN) deep learning algorithm with geometric transformations in combination with multi-camera/multi-image fusion technology. The system successfully tracked every individual in groups of unmarked mice and was applied to investigate chasing behavior. The proposed system constitutes a step forward in the noninvasive tracking of individual mice engaged in social behavior.