Experimental Animals最新文献

Alzheimer's disease (AD), a progressive neurodegenerative disease characterized by cognitive dysfunction and neuropsychiatric symptoms, is the most prevalent form of dementia among the elderly. Amyloid aggregation, tau hyperphosphorylation, and neural cell loss are the main pathological features. Various hypotheses have been proposed to explain the development of AD. Some therapeutic agents have shown clinical benefits in patients with AD; however, many of these agents have failed. The degree of neural cell loss is associated with the severity of AD. Adult neurogenesis, which governs cognitive and emotional behaviors, occurs in the hippocampus, and some research groups have reported that neural cell transplantation into the hippocampus improves cognitive dysfunction in AD model mice. Based on these clinical findings, stem cell therapy for patients with AD has recently attracted attention. This review provides past and present therapeutic strategies for the management and treatment of AD.

Humanized mice are widely used to study the human immune system in vivo and investigate therapeutic targets for various human diseases. Immunodeficient NOD/Shi-scid-IL2rγ^null (NOG) mice transferred with human hematopoietic stem cells are a useful model for studying human immune systems and analyzing engrafted human immune cells. The gut microbiota plays a significant role in the development and function of immune cells and the maintenance of immune homeostasis; however, there is currently no available animal model that has been reconstituted with human gut microbiota and immune systems in vivo. In this study, we established a new model of CD34⁺ cell-transferred humanized germ-free NOG mice using an aseptic method. Flow cytometric analysis revealed that the germ-free humanized mice exhibited a lower level of human CD3⁺ T cells than the SPF humanized mice. Additionally, we found that the human CD3⁺ T cells slightly increased after transplanting human gut microbiota into the germ-free humanized mice, suggesting that the human microbiota supports T cell proliferation or maintenance in humanized mice colonized by the gut microbiota. Consequently, the dual-humanized mice may be useful for investigating the physiological role of the gut microbiota in human immunity in vivo and for application as a new humanized mouse model in cancer immunology.

Pancreatic fibrosis (PF) is a hallmark of chronic pancreatitis (CP), but its molecular mechanism remains unclear. This study was conducted to explore the role of Kruppel-like factor 4 (KLF4) in PF in CP mice. The CP mouse model was established using caerulein. After KLF4 interference, pathological changes in pancreatic tissues and fibrosis degree were observed by hematoxylin-eosin staining and Masson staining, and levels of Collagen I, Collagen III, and alpha-smooth muscle actin, inflammatory cytokines, KLF4, signal transducer and activator of transcription 5A (STAT5) in pancreatic tissues were measured by enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, Western blot assay, and immunofluorescence. The enrichment of KLF4 on the STAT5 promoter and the binding of KLF4 to the STAT5 promoter were analyzed. The rescue experiments were performed by co-injection of sh-STAT5 and sh-KLF4 to confirm the regulatory mechanism of KLF4. KLF4 was upregulated in CP mice. Inhibition of KLF4 effectively attenuated pancreatic inflammation and PF in mice. KLF4 was enriched on the STAT5 promoter and enhanced the transcriptional and protein levels of STAT5. Overexpression of STAT5 reversed the inhibitory role of silencing KLF4 in PF. In summary, KLF4 promoted the transcription and expression of STAT5, which further facilitated PF in CP mice.

Autoimmune hepatitis (AIH) is a kind of autoimmune disease mediated by T cells, and its incidence is gradually increasing in the world. Oroxylin A (OA) is one of the major bioactive flavonoids that has been reported to inhibit inflammatory. Here, an AIH model of mouse was induced by Concanavalin A (Con A). It found that serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were decreased in mice with the treatment of OA. Hematoxylin-eosin staining showed that the liver injury was attenuated by OA, and TUNEL staining indicated that the cells apoptosis of liver was weakened in mice with OA treatment. ELISA analysis of cytokines and chemokines suggested that OA reduced the expression of IL-6, IL-17A, chemokine ligand 2 (CCL2), C-X-C motif chemokine ligand 1 (CXCL1) and CXCL10, but promoted the expression of IL-10 and TGF-β in mice. The mRNA levels of Il-17a in liver and spleen tissues were also significantly decreased, on the contrary, the mRNA levels of Il-10 in liver and spleen tissues were increased. The proportion of Treg/Th17 detected by flow cytometry revealed that OA promoted the differentiation of Treg and inhibited the differentiation of Th17 both in the liver and spleen. The results of this study demonstrated the inhibitory effects of OA on AIH-induced liver injury and the inflammatory response of AIH, and revealed that OA affected the balance of Treg/Th17 and shifted the balance toward Treg differentiation. It provided new potential drugs for the prevention of AIH.

Diabetic retinopathy (DR), a common complication of diabetes, involves excessive proliferation and inflammation of Muller cells and ultimately leads to vision loss and blindness. SRY-box transcription factor 9 (SOX9) has been reported to be highly expressed in Müller cells in light-induced retinal damage rats, but the functional role of SOX9 in DR remains unclear. To explore this issue, the DR rat model was successfully constructed via injection with streptozotocin (65 mg/kg) and the retinal thicknesses and blood glucose levels were evaluated. Müller cells were treated with 25 mmol/l glucose to create a cell model in vitro. The results indicated that SOX9 expression was significantly increased in DR rat retinas and in Müller cells stimulated with a high glucose (HG) concentration. HG treatment promoted the proliferation and migration capabilities of Müller cells, whereas SOX9 knockdown reversed those behaviors. Moreover, SOX9 knockdown provided protection against an HG-induced inflammatory response, as evidenced by reduced tumor necrosis factor-α, IL-1β, and IL-6 levels in serum and decreased NLRP3 inflammasome activation. Notably, SOX9 acted as a transcription factor that positively regulated thioredoxin-interacting protein (TXNIP), a positive regulator of Müller cells gliosis under HG conditions. A dual-luciferase assay demonstrated that SOX9 could enhance TXNIP expression at the transcriptional level through binding to the promoter of TXNIP. Moreover, TXNIP overexpression restored the effects caused by SOX9 silencing. In conclusion, these findings demonstrate that SOX9 may accelerate the progression of DR by promoting glial cell proliferation, metastasis, and inflammation, which involves the transcriptional regulation of TXNIP, providing new theoretical fundamentals for DR therapy.

Chicken embryos (CE) are an experimental model used as an important life science research tool worldwide, and then, adequate anesthetic protocols must be adopted to avoid the unjustifiable suffering of animals. Thus, our objective was to evaluate different anesthetic protocols in CEs using an easy inoculation route, the shell membrane (SM). We adopted the heart rate by pulse and the CE movements as a parameter of pain by assessing the vase in the chorioallantoic membrane (CAM) through the shell by a sensor of a multiparametric monitor. CEs were distributed into the following groups: (i) association of ketamine (5 mg/CE), midazolam (0.05 mg/CE) and morphine (0.15 mg/CE); (ii) ketamine (5 mg/CE) and xylazine (0.125 mg/CE); (iii) xylazine (0.0125 mg/CE) and morphine (0.15 mg/CE). The stress method used to test the anesthetic potential of the drugs was high temperature stimulation, keeping the CEs 10 cm from the fire of a Bussen nozzle for 30 s. In this experimental model, associations between different drugs decreased the pulse and the movement, indicating possible sedation. After treatment, the CE's submitted to the stress method had the heart rate and movements kept low in the groups ketamine-midazolam-morphine and ketamine-xylazine, while the non-drug-treated group increased heart rate. In a group treated with xylazine-morphine, the heart rate did not decrease, but the movement decreased after the stimulus. As the best results were the combinations of ketamine-midazolam-morphine and ketamine-xylazine, we recommend these associations for use in embryos in the final third of embryonic development in experimental protocols and euthanasia.

Spermatozoa released from the testis acquire fertilizing ability by translocating thorough the epididymis. Further, accessory gland secretions ejaculated into the female reproductive tract along with spermatozoa are also required to ensure male fecundity, such as the maintenance of proper sperm count and inhibition of premature sperm capacitation in the uterus. Here, we focus on a testis-enriched gene "Aldoart2", an epididymis-enriched gene "Serpina16", and seminal vesicle-enriched genes "Aoc1l3" and "Pate14" which were thought to be important for male fertility based on the previous studies. We independently deleted almost the entire protein-coding sequence of these genes in mice using CRISPR/Cas9. There were no overt defects in the histology and the sperm morphology and motility of any knockout (KO) mice. Further, Aoc1l3 and Pate14 KO males were able to form copulatory plugs. Finally, female mice that mated with these KO males delivered pups at a comparable level with the control males. Given our data, we demonstrated that the four genes predominantly expressed in the testis, epididymis, or seminal vesicle are independently dispensable for male fertility.

Metabolic-associated fatty liver disease (MAFLD) and alcoholic hepatitis (AH) are among the most prevalent liver diseases worldwide, and their coexistence is common in clinical practice. However, currently established models of MAFLD-AH coexistence do not fully replicate their pathological characteristics and require sophisticated experimental techniques. Therefore, we aimed to develop an easily replicable model that mimics obesity-induced MAFLD-AH in patients. Our goal was to establish a murine model that replicates MAFLD and AH coexistence, resulting in significant liver injury and inflammation. To this end, we administered a single ethanol gavage dose to ob/ob mice on a chow diet. The administration of a single dose of ethanol led to elevated serum transaminase levels, increased liver steatosis, and apoptosis in ob/ob mice. Furthermore, ethanol binge caused a significant increase in oxidative stress in ob/ob mice, as measured via 4-hydroxynonenal. Importantly, the single dose of ethanol also markedly exacerbated liver neutrophil infiltration and upregulated the hepatic mRNA expression of several chemokines and neutrophil-related proteins, including Cxcl1, Cxcl2, and Lcn2. Whole-liver transcriptomic analysis revealed that ethanol-induced changes in gene expression profile shared similar features with AH and MAFLD. In ob/ob mice, a single dose of ethanol binge caused significant liver injury and neutrophil infiltration. This easy-to-replicate murine model successfully mimics the pathological and clinical features of patients with coexisting MAFLD and AH and closely resembles the transcriptional regulation seen in human disease.

A-kinase anchoring protein 12 (AKAP12) has been identified as an anti-inflammatory and anti-fibrotic regulator in chronic inflammation and cardiovascular disease. However, the potential of AKAP12 in autoimmune disorders, rheumatoid arthritis (RA) and associated cardiac complications remains elusive. Here, a murine model of collagen-induced arthritis (CIA) was successfully induced, followed by adenovirus-mediated AKAP12 short hairpin RNA (shRNA) treatment. AKAP12 silenced mice displayed elevated clinical arthritis scores and significant ankle joint swelling. AKAP12 loss in CIA mice increased inflammatory cell infiltration and cartilage erosion, increased the levels of anti-IIC IgG and inflammatory cytokines IL-1β, IL-6, tumor necrosis factor (TNF)-α in serum, and upregulated the expression of cartilage-degrading enzymes MMP-1, MMP-3, MMP-13 in synovium, but reduced IL-10. The number of M1 macrophages and the expression of the markers (CCR7, IL-6, TNF-α and iNOS) was enhanced in synovial tissues, while M2 polarized macrophages and the makers (IL-10 and arginase-1) were reduced in response to AKAP12 loss. Moreover, low expression of AKAP12 was detected in the hearts of CIA mice. Loss of AKAP12 results in increased cardiac inflammation and fibrosis. This work suggests that AKAP12 loss aggravates joint inflammation likely through the promotion of M1 macrophage polarization and exacerbates inflammation-caused cardiac fibrosis.