Experimental Animals最新文献

There are few ultrasonographic studies on the spontaneous type 2 diabetes mellitus db/db mouse. Our objective was to dynamically investigate and assess renal morphological and hemodynamic changes in spontaneous T2DM db/db mice through high-frequency ultrasound. Eighteen male db/db mice (the model group) and twelve male db/+ mice (the control group) were included. Body weight and fasting blood glucose were measured at the ages of 8, 16 and 32 weeks. High-frequency ultrasound examinations were conducted at the same ages. Compared with those in the control group, hematoxylin-eosin and Masson staining revealed pathological changes in the renal tissue of the db/db mice at 16 weeks of age, and the lesions were significantly aggravated at 32 weeks of age. The body mass of the mice in the model group increased significantly at 8, 16 and 32 weeks of age, and the kidney volume measured by ultrasound also increased with age. Compared with those of the control group, the blood flow scores determined via power Doppler were significantly different. The peak systolic velocity (PSV), end diastolic velocity (EDV), and resistive index (RI) of the renal artery and the PSV, EDV, and RI of the segmental artery were significantly different at the sixteenth week compared with those that at the eighth week. The results of high-frequency ultrasound revealed that the renal hemodynamics of db/db mice changed at the sixteenth weeks.

Beige adipocytes arise from white adipocytes in response to cold or other stimuli, known as browning of white adipose. Beige adipocytes play a role similar to that of brown adipocytes, express high levels of uncoupling protein 1 (UCP1), and are responsible for energy consumption via heat production, thus aiding in fat loss. Although histidine (His) and soy isoflavones (Iso) co-ingestion reportedly reduces food intake, body weight, and fat accumulation in female rats, the underlying mechanism remains unclear. Therefore, this study aimed to elucidate the mechanisms whereby histidine and soy isoflavones (His-Iso) co-ingestion suppresses fat accumulation. Female rats were fed a control diet or diet containing Iso, His, or His-Iso for 2 weeks, followed by sampling of periovarian white adipose tissue (poWAT) and retroperitoneal white adipose tissue (rWAT) and adipocyte morphology analysis. Additionally, the expression of browning- and lipid metabolism-related genes was examined. Histochemical analysis revealed the presence of multilocular lipid droplets, representative of beige adipocytes, in the poWAT and rWAT of rats in the His-Iso co-ingestion group. Quantitative PCR analysis showed that His-Iso co-ingestion upregulated brown adipocyte and beige adipocyte markers, including UCP1, indicating that His-Iso intake induces beige adipocytes. Moreover, His-Iso co-ingestion upregulated genes related to fatty acid oxidation (carnitine palmitoyl transferase 1A) and lipolysis (adipose triglyceride lipase) in WATs. In conclusion, His-Iso co-ingestion increases UCP1 expression and morphological changes to beige adipocytes, and suppresses fat accumulation by promotion of lipolysis and fatty acid oxidation in WAT.

Atopic dermatitis (AD) is a chronic skin disease that causes itching and is characterized by recurrent flares and remissions. The interactions among type 2 inflammation, skin barrier dysfunction, and pruritus play important roles in the pathogenesis of AD. AD symptoms persist for a long period; thus, it is desirable to have disease models that reproduce a prolonged AD-like phenotype. Although MC903-induced AD model mice reportedly exhibit type 2 inflammation, skin barrier dysfunction, and pruritus, the effects of long-term application of MC903 on the changes in these symptoms over time are not fully understood. To clarify this point, we conducted a long-term time course analysis of these symptoms by applying MC903 to the ears of mice every other day for four weeks. Increased ear thickness, transepidermal water loss, number of scratching events, and serum IgE levels were observed in the MC903 model. Histological analysis revealed the infiltration of granulocytes and CD3-positive T cells and an increase in mast cells in the dermis. Furthermore, analyses of mRNA and protein expression in ear tissue revealed increased expression of thymic stromal lymphopoietin, IL-4, IL-13, and IL-33, which are involved in type 2 inflammation. All these changes were observed within two weeks after the initial application of MC903 and thereafter persisted throughout the experimental period. In conclusion, our data indicate that the long-term application of MC903 prolongs the duration of the three major symptoms of AD.

The Adriamycin-induced nephropathy (AN) model plays a crucial role in advancing our understanding of and research on chronic kidney disease (CKD). This review outlines methodologies for generating AN models in mice and rats, discusses their pathophysiologic and molecular characteristics, highlights their advantages and limitations, describes therapeutic interventions that have been evaluated in these models, and presents future research perspectives. The AN model replicates key features observed in human CKD, such as proteinuria, podocyte injury, glomerulosclerosis, and tubulointerstitial fibrosis. Notably, genetic factors significantly influence the onset and severity of AN, with mutations in the Prkdc gene linked to nephrotoxicity and systemic toxicity. To evaluate therapeutic interventions for CKD, agents such as ACE inhibitors, corticosteroids, and SGLT2 inhibitors have been tested in the AN model, demonstrating promising renoprotective effects. However, the systemic toxicity of Adriamycin and variability across models pose limitations, highlighting the need for caution when translating findings to human CKD. Future advancements in genetic engineering and the application of CRISPR-Cas9 technology are expected to improve the fidelity of AN models to human disease. Additionally, discovery of biomarkers by using the AN model enables us to improve early diagnosis. These efforts are anticipated to deepen our understanding of CKD pathophysiology and contribute to developing more effective diagnostic tools and targeted therapies.

At present, there lacks a definitive pharmaceutical intervention or therapeutic approach for diabetes-associated cognitive impairment. Herein, we delved into the impact of electroacupuncture on cognitive function in high-fat diet/streptozocin (HFD/STZ)-induced type 2 diabetes mellitus (T2DM) mice and underlying mechanisms. Hippocampal insulin resistance was determined by western blot analysis. Cognitive function was evaluated by Morris water maze test. The morphology of the hippocampal neurons was observed through hematoxylin & eosin staining and Nissl staining. Synaptic plasticity was assessed by western blot analysis. Immunofluorescence, immunohistochemistry, western blot and real-time PCR were employed to detect the levels of ferroptosis markers, autophagy markers, and netrin-1. Electroacupuncture treatment exhibited ameliorative outcomes on hippocampal insulin resistance, spatial learning, memory function, neuronal damage, and synaptic plasticity in T2DM mice. Furthermore, it effectively suppressed neuronal ferroptosis in the hippocampus by upregulating GPX4 and SLC7A11 expression, and reducing 4-HNE expression. Meanwhile, electroacupuncture intervention increased the levels of Beclin1 and LC3II/LC3I, as well as decreased the levels of p62 and phosphorylated-mTOR in the hippocampus of T2DM mice, suggesting that electroacupuncture facilitated autophagy activation by inhibiting mTOR activity. 3-MA-mediated autophagy inhibition undermined the beneficial effects of electroacupuncture on neuronal ferroptosis and cognitive deficits in T2DM mice. Additionally, the beneficial effects of electroacupuncture on autophagy and ferroptosis was achieved by upregulation of netrin-1 in the hippocampus. Our study revealed that electroacupuncture therapy inhibited neuronal ferroptosis via the activation of autophagy, thereby ameliorating cognitive deficits in T2DM mice.

Gracile axonal dystrophy (gad) mutant mice present with autosomal recessive inherited sensory ataxia in the early stages, followed by age-dependent motor ataxia. This phenotype is caused by a mutation in the ubiquitin carboxyl-terminal hydrolase isozyme L1 (UCH-L1) gene and leads to a lack of expression of UCH-L1 protein, ubiquitin-proteasome which is related to the autophagy pathway and the ubiquitin-proteasome system (UPS). To elucidate the pathophysiology of abnormal protein accumulation in gad mice, we focused on macroautophagy. Using electron microscopy, we detected a double-membrane structure, which was characteristic of autophagosomes, in gad mice. In addition, in immunohistochemistry to investigate the expression levels of autophagy-related proteins in the gracile nuclei of the gad mouse, we found upregulation of LC3 and p62 but not LAMP-2A. These results suggested that a lack of UCH-L1 expression might induce the formation of autophagosomes, but the resulting autophagy flux might be disturbed.

This study aimed to determine the feasibility of using perfusion computed tomography (CT) to assess blood flow in different regions of the stomach in dogs. Dynamic perfusion CT scans were conducted on five beagle dogs, and blood flow analysis was performed using the maximum slope and Patlak plot methods. The findings revealed significant variations in blood flow among the fundus, body, and pylorus of the stomach. Specifically, the body showed approximately 1.3 times higher blood flow than the fundus and approximately 5 times higher blood flow than the pylorus. There were no significant differences in blood flow between the two analysis algorithms. The findings suggest that gastric perfusion CT can accurately detect variations in blood flow within the stomach. Using the maximum slope method for analysis allows for noninvasive and rapid measurement of gastric blood flow. This technique may have clinical applications in detecting submucosal diseases that are challenging to identify with endoscopies and serve as a valuable noninvasive tool for longitudinal observations in experimental animal studies.

This study evaluated the therapeutic potential of omentin-1 in preeclampsia (PE). A PE-like mouse model received recombinant human omentin-1 protein (rh-omentin) from gestation day (gd) 13.5 to 16.5. On gd 17.5, fetuses and placentas were weighed, and soluble fms-like tyrosine kinase-1 (sFlt-1) levels were measured. Maternal aortic rings were used for ex vivo vascular reactivity assays. Inflammatory factors and Krüppel-like factor 2 (KLF2) expression in placental and aortic tissues were assessed using qPCR. Human umbilical vein endothelial cells (HUVECs) were exposed to plasma from PE patients or healthy pregnant individuals to evaluate omentin-1 and KLF2 expression by qPCR, with additional evaluation of KLF2 after rh-omentin treatment. Rh-omentin treatment reduced blood pressure in the PE-like model, accompanying by increased fetal and placental weights and higher fetal/placental weight ratios compared to untreated PE mice. Additionally, rh-omentin enhanced endothelial function in maternal aortic rings, as well as reduced placental necrosis and promoted CD31-positive vasculature in the labyrinth zone. Moreover, rh-omentin decreased pro-inflammatory factors in aortic and placental tissues of PE mice. KLF2 expression was restored in both aortic and placental tissues of PE mice and in HUVECs exposed to PE plasma following rh-omentin treatment. Rh-omentin improved fetal and placental outcomes in PE-like mice, enhancing vascular function and reducing inflammation in aortic and placental tissues. It also restored KLF2 expression in PE tissues and HUVECs exposed to PE plasma, suggesting therapeutic potential for addressing endothelial dysfunction in PE.

Status epilepticus is linked to cognitive decline due to damage to the hippocampus, a key structure involved in cognition. The hippocampus's high vulnerability to epilepsy-related damage is the main reason for this impairment. Convulsive seizures, such as those observed in status epilepticus, can cause various hippocampal pathologies, including inflammation, abnormal neurogenesis, and neuronal death. Interestingly, substantial evidence points to the therapeutic potential of the sedative/hypnotic agent zolpidem for neurorehabilitation in brain injury patients, following the unexpected discovery of its paradoxical awakening effect. In this study, we successfully established an ideal lithium-pilocarpine rat model of status epilepticus, which displayed significant deficits in hippocampal-dependent learning and memory. The Morris water maze test was used to assess zolpidem's potential to improve learning and memory, as well as its impact on anxiety-like behavior and motor function. Immunohistochemical staining and fluorescence analysis were used to examine the effect of zolpidem on K⁺-Cl^- cotransporter 2 (KCC2) and Na⁺-K⁺-Cl^- cotransporter 1 (NKCC1) protein expression in the hippocampal CA1 and CA3. Our findings showed that zolpidem did not improve learning and memory in status epilepticus rats. Additionally, its sedative/hypnotic effects were not apparent in the status epilepticus condition. However, immunohistochemical results revealed that zolpidem significantly restored altered NKCC1 levels in the CA1 and CA3 to levels similar to those seen in normal rats. These findings suggest that zolpidem may contribute to molecular restoration, particularly through its impact on NKCC1 protein expression in the hippocampus, which is crucial for proper inhibitory neurotransmission in the brain.

Allele-specific, monoallelic expression in diploid organisms represents an extreme case of allelic imbalance resulting from incompatibility between cis- and trans-elements. Due to haploinsufficiency, such monoallelic expression can lead to sporadic genetic diseases. In mice, allelic imbalances can be introduced into F1 offspring from inbred strains. Previously, we established F1 hybrid embryonic stem (ES) cell lines derived from four different mouse strains, each belonging to a different subspecies with substantial genetic polymorphisms. In this study, we investigated the neural differentiation capacity of the established ES cell lines. By introducing different culture conditions, which kept the ES cells undifferentiated under various pluripotencies, we succeeded in differentiating the majority of ES cell lines (eight out of eleven) with our default neural differentiation paradigm. Still, three lines exhibited insufficient differentiation despite combining culture conditions promoting undifferentiated as well as differentiated status. In addition, Ube3a imprinting was seen in two lines. Our findings contribute to the methodological understanding of mouse ES cell pluripotency and lead to the practical utility of F1 hybrid ES cells as a model for studying phenotypes resulting from gene locus interactions.