Abstract: Objective The aim of this study was to examine whether immune tolerance was reversed by trained immunity in both in vivo and in vitro models. Methods Glucan is a prototypical trained immunity inducer. To establish the in vitro trained immunity model, BMDMs were stimulated with 40 μg / mL β-glucan for 24 h. BMDMs were washed once with warm PBS. After 24 h, they were incubated for 6 days in culture medium that was changed once at day 3. Trained BMDMs were stimulated with 100 ng / mL LPS at day 7. To establish the in vivo trained immunity model, wildtype C57BL/6J mice were injected intraperitoneally with 1 mg β-glucan in 200 mL PBS. As a control, intraperitoneal injection of PBS alone was performed. After 7 days, mice were infected with Staphylococcus aureus intraperitoneally (1 × 10⁴ / 200 mL PBS per mice). BMDMs were stimulated with LPS to induce immune tolerance in vitro. β-glucan was added at 24 h post-LPS stimulation to reverse immune tolerance. Cytokine production capacity was determined by LPS restimulation. CLP was carried out in mice to induce immune tolerance in vivo. Intraperitoneal injection of 1 mg β-glucan was performed to reverse CLP-induced tolerance. The efficacy of tolerance reversal was reflected by the survival rate post-reinfection with non-lethal doses of bacteria or fungi. Results (1)Glucan-trained BMDMs produced higher levels of proinflammatory cytokines, such as TNF-α and IL-6, and more nitric oxide. The energy metabolism of trained macrophages shifted to aerobic glycolysis, leading to lactate accumulation and enhanced m-TOR activation. (2)β-glucan-induced trained immunity was protective in vivo. (3) β-glucan reversed LPS-induced immune tolerance in vitro. (4) Administration of β-glucan did not reverse the CLP-induced immune tolerance in the current experimental setting. Conclusion This study successfully established β- glucan trained immune models in vitro and in vivo, and demonstrated that β-glucan can reverse LPS-induced immune tolerance in vitro. However, the current Results have not confirmed that β-glucan can reverse CLP-induced immune tolerance in vivo and improve secondary infection survival.

Abstract: Objective To investigate the effects of aerobic exercise on the inhibitory synaptic plasticity of the ventral tegmental area (VTA) dopamine neurons of mice with nicotine withdrawal. Methods Eight-week-old male C57BL/ 6 mice were randomly divided into a saline sedentary (SS) group, saline exercise ( SE) group, nicotine sedentary (NS) group, and nicotine exercise (NE) group following the conditioned place preference (CPP) paradigm. During abstinence, SE and NE group mice were subjected to a moderate-intensity treadmill running protocol for 2 weeks. The CPP paradigm was used to test nicotine-seeking behavior of mice after nicotine withdrawal. The whole-cell patch clamp was used to record the spontaneous inhibitory postsynaptic current ( sIPSC), the miniature IPSC (mIPSC), and the IPSC paired-pulse ratio (PPR) of dopamine neurons in the VTA. Immunofluorescence staining was used to detect the expression of GAD67 in the VTA. Results (1) The CPP score was higher in the NS than SS group and lower in the NE than NS group. (2) The mean frequency and amplitude of the sIPSC were higher in the NS than SS group and lower in the NE than NS group. (3) The mean frequency and amplitude of the mIPSC were higher in the NS than SS group and lower in the NE than NS group. (4) At the 20 ms and 50 ms interstimulus intervals, the IPSC PPR was lower in the NS than SS group and higher in the NE than NS group. (5) The fluorescence intensity of GAD67 was lower in the NS than SS group and higher in the NE than NS group. Conclusions 2 weeks moderate intensity aerobic exercise reduces presynaptic GABA release, down-regulates the number and / or function of postsynaptic GABAA receptors in VTA dopamine neurons, and these decreased inhibitory synaptic transmission may represent a potential mechanism by which aerobic exercise attenuates nicotine seeking during abstinence.

Abstract: Objective We focused on solving a problem in the infection course of cecum ligation and puncture (CLP) septic model animals, i. e. , the random occlusion of ligation and puncture sites due to bowel edema. To establish a septic animal model with a sustainable infection, we combined cecal ligation puncture and bacterial carrier implantation with a compound infection stent. Methods Fifty-four male SD rats were randomly divided into three groups: Sham ( n= 18), CLP (n= 18), and multiple infect model (MIM,n= 18) groups. In each group, 10 rats were investigated for their survival status, intra-abdominal infection, and survival rate. Another 8 rats were selected for studying related indicators of sepsis multiple organ dysfunction syndrome (MODS) injury. The detected indicators included LPS, IL-6, cTn-I, ALT, AST, TBil, Lac, and Cr abdominal aortic blood contents; MDA and ATP liver tissue contents, and HE staining of pathological changes in heart, liver, lung, and kidney tissue. Results 96 h after molding operation, there were no deaths in the Sham group, and survival rates in the CLP and MIM groups were 70% and 0%, respectively. The degrees of injury in the heart, liver, lungs, and kidneys in the MIM group were greater than those in the CLP model group. Compared with the Sham and CLP groups, the MIM group had the highest contents of LPS, IL-6, cTn-I, ALT, AST, TBil, Cr, Lac, and MDA and the lowest of ATP, all of which were significantly different (P< 0. 05). The coefficients of variation for LPS, IL-6, TBil, and MDA in the MIM group were significantly decreased in relation to those of the CLP group. Conclusions The MIM group’s intestinal contents leaked continuously to cause persistent infection, which result ed in much lower variability in key infection and inflammation indicators (LPS, IL-6, MDA, etc. ) and a more consistent course of disease than in the CLP group. Thus, the structural validity of the MIM model was better. Compared with the CLP group, the MIM group had more severe postoperative infections, deeper organ damage, higher mortality, more consistent within-group death times, and thus had greater face validity. Therefore, the MIM model best fits with the clinical profile of septic-MODS, which is caused by an over-reaction to severe infection.

Abstract: Objective To explore the effects of matrine on gemcitabine (GEM) resistance in pancreatic cancer and to provide a new therapeutic strategy for restoring the chemosensitivity of pancreatic cancer cells. Methods The pancreatic cancer cell line AsPC-1 was selected and GEM resistance induced by treatment with gemcitabine. The drug- resistant cell line AsPC-1-GEM was established and confirmed by CCK-8. The effect of matrine on AsPC-1-GEM was analyzed by detecting the cell viability. Expression changes to multidrug resistance protein 2 (ABCG2) and the effect of matrine on ABCG2 were further tested using RT-PCR and Western Blot. We further established a GEM-resistant cell line xenograft model of pancreatic cancer in nude mice and observed the changes in tumor volume after treatment with matrine. The effect of matrine on the expression of ABCG2 was detected by immunohistochemistry. Results ABCG2 expression was increased in GEM-resistant AsPC-1 cells (P< 0. 01), and matrine significantly reduced ABCG2 expression (P< 0. 01) and improved the sensitivity of AsPC-1-GEM cells (P< 0. 01). Treatment with matrine reduced the expression of ABCG2 (P< 0. 01) and retarded tumor growth ( P< 0. 01) in the xenograft models with AsPC-1-GEM tumors. Conclusions Matrine increases the sensitivity of GEM-resistant pancreatic cancer cell lines by decreasing the expression of ABCG2.

Abstract: Objective To study the toxicity of a single administration and 3-month repeated administration of An’ erning (AEN) granules in juvenile SD rats, and evaluate the long-term safety in children. Methods 20 juvenile SD rats (3 ~ 4 weeks) were given the maximum administration dosage ( 240 g crude drug / kg). This was followed by an observation of toxicity reactions and death for 15 days. Juvenile SD rats (200) were divided into vehicle control, Aconitum tanguticum control, low-dose, middle-dose, and high-dose groups. Each group was composed of 40 rats ( half male and half female), each of which was given purified water, A. tanguticum (5. 5 g crude drug / kg), and AEN (3, 11, and 40 g crude drug / kg), all in a volume of 10 mL/ kg, for 91 days. Food intake and body weight were measured, and hematology, biochemistry, coagulation, urine, ophthalmologic, and histopathology examinations of 5,10 and 5 rats for each sex in each group were conducted mid-administration, upon drug withdrawal, and 4 weeks after withdrawal. Results No obvious toxic effects or deaths were recorded after the single administration of AEN. After the 3-month repeated administration of AEN, male rats in the high-dose group had decreased body weights, decreased food intake, reversibly increased NEUT count, NEUT ratio, MONO count, MONO ratio, and ALB, and reversibly decreased AST, Na⁺ , and Cl^- . Conclusions There were no obvious toxicity reactions in young rats given AEN granules. The relative safe dosage of AEN was 40 g crude drug / kg, and the no observed adverse effect level (NOAEL ) is 11 g crude drug / kg. The clinical administration of AEN is safe.

Abstract: Objective To observe spontaneous liver tumor formation in Mdr2 knockout mice with C57BL/ 6 background. Methods Five wild type C57BL/ 6 mice and nine Mdr2 knockout C57BL/ 6-Abcb4^tm1 mice aged ( 11. 3 ± 4. 2)weeks were sacrificed after 65 weeks of continuous feeding. Serum and liver samples were collected and serum ALT, AST, and AFP levels were measured. Paraffin-embedded sections of liver tissue were stained with HE and Sirius red. CK-7 and CK-19 expression in tumor and adjacent tissues was detected by immunohistochemistry. Results Nine Mdr2 knockout mice formed liver tumors spontaneously. Serum ALT, AST, and AFP levels were significantly higher than those in wildtype mice(P< 0. 01). CK-7 and CK-19 expression was negative in Mdr2 knockout mice. Conclusions The Mdr2 knockout mice formed liver tumors spontaneously when continuously fed to ( 76. 3 ± 4. 2 ) weeks of age, and their pathological classification was hepatocellular carcinoma.

Abstract: Objective A mouse orthotopic transplanted tumor model of lung cancer was established to simulate the occurrence and development of lung cancer in clinical patients. Methods The LLC cell line expressing a luciferase reporter gene was established (LLC-luc). LLC-luc cells were injected into the left lung of mice to establish an orthotopic tumor model. CT and in vivo fluorescence imaging were used for tracer monitoring of the orthotopic tumor model. Lung tumors were collected on day 14 after cell injection. The characteristics of tissue immunology and the immune microenvironment were assessed by IHC. Results After LLC-luc cell injection, a tumor had formed in the left lung. The tumor has a metastatic potential and immune cell infiltration was detected. Conclusions We successfully established a mouse model of orthotopic lung cancer, which is simple to evaluate and mimics the development of lung cancer in clinical patients.

Abstract: Objective This study intended to establish rat venous replacement models through the “ cannula method ” and “ anastomosismethod ” and to identify a safe and effective venous replacement model for studies into the pathological mechanisms related to venous replacement. Methods SPF BN rats were used. The venous replacement models were constructed using the cannula or anastomosis method. The total operation time, blood flow blockage time and the 48 h survival rates after surgery were measured and analyzed. Abdominal vascular ultrasound was performed to observe the patency and blood flow velocity changes. The rats were killed to obtain the graft at different timepoint. Pathological changes were evaluated by histopathology, and TGF-β1 expression was detected by q-PCR. Results 36 rats with venous replacement were established via the cannula method or anastomosis method. There was no significant difference in the 48- hour survival rates [100. 0% (18 / 18) vs 94. 4% (17 / 18), P= 0. 310]. The total operation time and blood flow blocking time of the cannula method were shorter than that of the anastomosis method [(35. 8 ± 3. 6) min vs (56. 8 ± 4. 9) min, P< 0. 05;(14. 6 ± 2. 9) min vs ( 35. 1 ± 4. 5) min, P< 0. 05]. The vein blood flow velocity in the transplantation section increased in the early stage and gradually decreased with postoperative time. At 4 weeks, blood flow velocity in the cannula group was significantly lower than that in the anastomosis group (P< 0. 05). At 4 weeks after the operation, the formation of venous collateral circulation was seen around the vein of the transplanted section of models in the cannula group, but the transplanted vein was still unobstructed. There was no obvious formation of venous collateral circulation in the anastomotic group within 4 weeks. With the advancement of postoperative time, the wall of the transplanted vein thickened and the diameter reduced gradually in the two groups. The vein diameter was smaller in the cannula group than in the anastomosis group at each timepoint after the operation (P< 0. 05). In the cannula group, cellulose deposition was observed on the outer layer of the vein wall, forming fiber cladding in the muscle layer and intima hyperplasia and lumen stenosis. The degree of infiltration of mononuclear cells and CD4+ T lymphocytes in the transplanted vein wall in the anastomotic group was significantly higher than that in the cannula group (P< 0. 05 ). With the advancement of postoperative time, the expression of TGF-β1 in the vein wall of the transplanted section of the two groups increased gradually. At each timepoint, TGF-β1 expression in the cannula group was higher than that in the anastomosis group (P< 0. 05). Conclusions Both the cannula and anastomosis method can be used to safely and effectively establish a rat inferior vena cava replacement model. Compared with the cannula method , the vein replacement model established by the anastomosis method has lighter non-specific verification and wall remodeling, and has a higher long-term patency rate, which is more suitable for experimental studies related to vein replacement.

Abstract: Objective To promote resource information sharing in the field of laboratory animals and meet the needs of various levels and research purposes, national infrastructure for an animal model resource platform was established to meet the needs of both the supplier and customer. Methods We issued a collection letter for laboratory animal and animal model resources, collected laboratory animals and animal model resources nationwide, and supplemented related resources from the literature and public databases. Results The national infrastructure for an animal model resource platform systematically collected and arranged laboratory animal resources, animal models, and related product information, covering the development, identification, evaluation and application of laboratory animals and animal models, as well as exclusive reagents, instruments, and equipment for animal experiments, and science and technology outsourcing services based on animal experiments. We promoted resource sharing through the network platform and provided data support for drug screening and treatment. Conclusions In this study, we established national infrastructure for an animal model resource platform to provide one-stop services such as enquiries for laboratory animals and relevant resource information, release of information on supply and demand units, and display of detailed information to provide high-quality scientific and technological laboratory animal and animal model resource sharing services for scientific and technological innovation and social development.

Abstract:With the rapid advancement of next-generation sequencing ( NGS ), sequencing and its related technologies are becoming more mature and providing higher accuracy and throughput. Traditional method of sequencing require a large sample quantity that is difficult to obtain for some samples. Thus, techniques with a lower demand on sample quantity are in urgent need. In library construction, the Tn5 transposase cuts DNA and adds an adapter sequence to both sides of the target sequence, which requires fewer steps and a lower sample quantity. Therefore, applications of Tn5 transposase have been gradually developed in biotechnology. For example, CUT&Tag, stLFR, and TRACE-seq are techniques that use Tn5 transposase in epigenomic sequencing, long fragment reading, and transcriptome sequencing. The simple steps and very low cost make the techniques popular. In this review, we summarize the Tn5 transposon and its applications in biotechnology to make it understood more easily and provide a reference for improvement and promotion in the future.

Abstract:Diurnal rodents and humans share similar circadian rhythms. Since the discovery of the circadian clock, scientists have gradually recognized that diurnal rodents exhibit irreplaceable advantages over nocturnal rodents. Recently, they have been exploited as novel models in medical fields such as metabolism, light reflection, neurology regulation, and social behavior. However, diurnal rodents are poorly understood in China. In this paper, we discuss the evolution of circadian rhythms in diurnal animals and the mechanisms behind these animals’ temporal niches. Moreover, to provide an information source for chronobiology, the locomotor activity and application of four well-defined diurnal rodents, Meriones unguiculatus, Octodon degus, Arvicanthis niloticus, and Ammospermophilus leucurus, are reviewed.

Abstract:Iron is the most abundant metal element in the brain, and iron homeostasis ensures normal physiological functions occur in this organ. When iron metabolism is disrupted in the brain, excess iron promotes the formation of free radicals and oxidative stress, leading to neuronal death. To fully study cerebral iron deposition diseases, animal models need to be established. This article reviews different modeling method , experimental mouse species, and iron types, and provides a reference for the establishment of brain iron deposition models.

Abstract:Domestic dogs are highly integrated into human society and ecology, and have become a natural model animal for analyzing cognitive evolution theory, conducting comparative cognitive research, and conducting human cognitive dysfunction disease research. Functional magnetic resonance imaging ( fMRI) is a non-invasive and safe neuroimaging technique that can reveal the temporal and spatial distribution of biological brain neural activities. In recent years, fMRI has been used to study the neural mechanisms of behavioral cognitive characteristics in domestic dogs. This paper provides an introduction to the fMRI technique. We reveal how the neural mechanisms of dog cognition were studied using fMRI of dog brains to locate the activated functional brain areas under different experimental paradigms, such as vision, smell, and hearing. The technical and method ological challenges of fMRI in canine cognitive research are also summarized. This paper provides a theoretical basis and reference for researchers who carry out cognition studies on domestic dogs and other animals.

Abstract:Rheumatoid arthritis ( RA ) is a complex autoimmune disease characterized by severe joint inflammation, synovial hyperplasia, and cartilage and bone destruction. Based on our understanding of RA and the theories of traditional Chinese and Western medicine, this paper presents the existing RA animal models and analyzes the modeling method , mechanisms, model evaluation indicators, clinical symptom coincidences, advantages and disadvantages, and model applicability to provide a reference for the establishment of better RA animal models.

Abstract:Acute exacerbation of chronic obstructive pulmonary disease ( AECOPD) refers to the continuous deterioration of chronic obstructive pulmonary disease (COPD) beyond the scope of daily variation. At present, there are no standard animal models for COPD or AECOPD. The animal model for AECOPD is applied in studying the pathological mechanisms of AECOPD and determining effective diagnosis and treatment method. COPD preparation method include simple passive smoking, passive smoking combined with tracheal instillation of the lipopolysaccharide method, and automobile exhaust inhalation. AECOPD model preparation is usually bacterial or viral infection of the COPD model. This brief review focuses on COPD and AECOPD animal models from the perspectives of model creation and evaluation, providing useful information for researchers and medical practitioners.

Abstract:The apolipoprotein E (ApoE) is involved in cholesterol and lipid metabolism in the brain, transporting cholesterol to neurons and removing lipid debris to facilitate myelin repair. ApoE4, one of three subtypes of ApoE, is the most important genetic risk factor for sporadic Alzheimer’s disease (AD). ApoE4 increases the deposition and reduces the clearance rate of Aβ, enhances hyperphosphorylation of Tau protein, induces abnormal lipid metabolism in the brain, and impairs the brain and blood-brain barrier. ApoE4 transgenic mice were used to study AD pathogenesis and prevention. ApoE4 transgenic mice showed decreased abilities in spatial learning and memory at the age of 9 months and a pathological phenotype related to β-amyloid at 2 ~ 4 months. At 4 months, total Tau and phosphorylated Tau levels increased, and a loss of neurons and damage to dendrites and synapses occurred in the hippocampus. ApoE4 transgenic mice have been used to study the prevention and treatment of AD drugs such as the GABA neuronal receptor agonist pentobarbital, the glutamine antagonist JHU-083, epidermal growth factor, inulin, and curcumin. This review provides a reference for those applying ApoE4 transgenic mice in AD research

Abstract:Autism spectrum disorder (ASD) is a range of neurodevelopmental disorders characterized by social and communication problems and repetitive and restrictive behaviors. The phenotypic heterogeneity of ASD makes it particularly difficult to determine the exact etiology and pathophysiology behind the core symptoms, which are usually accompanied by complications such as ADHD, seizures, and sensorimotor abnormalities. Animal models provide important platforms for clarifying the etiology and pathogenesis of diseases. More and more studies are using animal models induced by environmental exposure and maternal immune activation to explore the etiology and pathogenesis of ASD and screen for drug targets. This paper reviews the different neural network mechanisms, changes to brain tissue and related factors, symptom phenotypes, and other aspects of common animal models to provide a reference for those clarifying the neurobiology of ASD and developing potential drugs or therapeutic interventions, and to help with selecting targeted animal models for future precision experimental research.