Background: Therapy in the latent period is favorable for retarding the process of epileptogenesis. Recently, we have discovered that the activated sigma-1 receptor (Sig-1R) attenuates the hippocampus pathological injury and memory impairment in the latent period of epileptogenesis. But the molecular mechanism needs further investigation.
Methods: PRE-084 was utilized as a research tool to highly selectively activate Sig-1R in epileptic mice. After the treatment of PRE-084, the pro-inflammatory cytokines, neuropathological traits, and the level of mitochondrial translocator assembly and maintenance 41 homolog (TAMM41) in the hippocampus were examined. The mode in which the Sig-1R interacts with TAMM41 was explored. The role of TAMM41 in the protecting effect of PRE-084 was established.
Results: PRE-084 inhibited the growth of pro-inflammatory cytokines, reduced the formation of gliosis, alleviated neuronal damage in the hippocampus, and attenuated memory impairment in the latent period of epileptogenesis. The protein level of TAMM41 decreased in the hippocampi of epileptic mice and increased in the PRE-084-treated mice. The Sig-1R bound with TAMM41 directly, maintaining the stability of TAMM41. Knockdown of TAMM41 reversed the protective effect of PRE-084, and overexpression of TAMM41 exhibited a similar protective action to that of PRE-084.
Conclusion: We presented the concept of the “sigma-1 receptor-TAMM41 axis” and proposed that augmenting this axis can attenuate neuroinflammation and memory impairment in the process of epileptogenesis.
Background: Besides seizures, a myriad of overlapping neuropsychiatric and cognitive comorbidities occur in patients with epilepsy, which further debilitates their quality of life. This study provides an in-depth characterization of the impact of brivaracetam and rufinamide individually and in combination at 10 and 20mg/kg doses, respectively, on corneal kindling-induced generalized seizures and behavioral alterations. Furthermore, observed convulsive frequency and behavioral changes were correlated to post-kindling-induced changes in the activity of markers of oxidative stress.
Methods: Adult C57BL/6 mice were kindled via twice-daily transcorneal 50-Hz electrical stimulations (3mA) for 3s for 12days until animals reached a fully kindled state. After the kindling procedure, animals were tested using a set of behavioral tests, and neurochemical alterations were assessed.
Results: Corneal-kindled animals exhibited intense generalized convulsions, altered behavioral phenotypes typified by positive symptoms (hyperlocomotion), negative symptoms (anxiety and anhedonia), and deficits in semantic and working memory. BRV 10+RFM 20 dual regime increased convulsive threshold and propensity toward the start of stage 4–5 seizures and improved phenotypical deficits, that is, anxiety, depression, and memory impairments. Moreover, this combination therapy mitigated kindling-induced redox impairments as evidenced by reduced malondialdehyde and acetylcholinesterase levels and increased glutathione antioxidant activity in the brain of animals subjected to repetitive brain insult.
Conclusion: Based on our outcomes, this dual therapy provides supporting evidence in alleviating epilepsy-induced neurobehavioral comorbidities and changes in redox homeostasis.
Background: Scientific evidence to guide clinicians on the use of different antiseizure drugs in combination therapy is either very limited or lacking. In this study, the impact of lacosamide and perampanel alone and in combination was tested in corneal kindling model in mice, which is a cost-effective mechanism for screening of antiseizure drugs.
Methods: The impact of lacosamide (5mg/kg) and perampanel (0.125mg/kg) alone and their combination was tested in corneal kindling process (3-mA current for 3s applied twice daily for consecutive 12days) in male BALB/c mice. Post-kindling, mice were subjected to a battery of behavioral tests assessing anxiety, memory, and depression-like behaviors. Brain tissues were then harvested for analysis of oxidative stress biomarkers.
Results: Our results showed that the combination therapy of lacosamide and perampanel was more effective in reducing seizure progression than monotherapy of these drugs. Animals treated with combination therapy showed significant behavioral improvements, as reduced anxiety and depression were noticed, and their cognitive abilities were notably better compared to animals of all other groups. Moreover, biochemical assays of isolated brains from combination-treated group revealed lesser amount of oxidative stress. In addition, outcomes of dual regime were comparable to the phenytoin in seizure control but showed superior benefits in mitigation of kindling-prompted behavioral dysfunction and oxidative stress.
Conclusions: This study suggests that the lacosamide and perampanel combination therapy worked noticeably better in halting the corneal kindling process in mice and improved the epilepsy-associated psychiatric disorders that might be due to antioxidant effects of both drugs.
The increasing incidence of neurodegenerative diseases (NDs) and the constraints of existing treatment methods have spurred a keen interest in investigating alternative therapies. Medicinal plants, renowned for their long-standing use in traditional medicine, offer a hopeful avenue for discovering new neuroprotective agents. This study emphasizes the potential neuroprotective characteristics of edible fruit plants in Bangladesh, specifically focusing on their traditional folk medicine uses for neurological disorders. This study provides an in-depth overview of the different types of edible fruit trees in Bangladesh and their phytochemicals, including flavonoids, terpenoids, and phenolic acids. This work examines the scientific data supporting the neuroprotective properties of bioactive chemicals from plants. It further explores the mechanisms by which these compounds work to counteract oxidative stress, decrease inflammation, and stimulate neurogenesis. Moreover, the study investigates toxicological characteristics and bioactive components of some fruits, emphasizing the importance of further investigation to measure their safety profile comprehensively. This thorough study highlights the potential benefits of Bangladesh’s edible fruit trees as a rich source of neuroprotective chemicals. It also shows that additional research might lead to novel approaches for improving brain functioning and preventing NDs.
Polyphenols, a diverse group of naturally occurring compounds found in plants, have garnered significant attention for their potential therapeutic properties in treating neurodegenerative diseases (NDs). The Wnt/β-catenin (WβC) signaling pathway, a crucial player in neurogenesis, neuronal survival, and synaptic plasticity, is involved in several cellular mechanisms related to NDs. Dysregulation of this pathway is a hallmark in the development of various NDs. This study explores multiple polyphenolic compounds, such as flavonoids, stilbenes, lignans, and phenolic acids, and their potential to protect the nervous system. It provides a comprehensive analysis of their effects on the WβC pathway, elucidating their modes of action. The study highlights the dual function of polyphenols in regulating and protecting the nervous system, providing reassurance about the research benefits. This review provides a comprehensive analysis of the results obtained from both in vitro studies and in vivo research, shedding light on how these substances influence the various components of the pathway. The focus is mainly on the molecular mechanisms that allow polyphenols to reduce oxidative stress, inflammation, and apoptotic processes, ultimately improving the function and survival of neurons. This study aims to offer a thorough understanding of the potential of polyphenols in targeting the WβC signaling pathway, which could lead to the development of innovative therapeutic options for NDs.
Background: The chicken chorioallantoic membrane (CAM) model is a potential alternative to the mouse model based on the 3R principles. However, its value for determination of the in vivo behaviors of radiolabeled peptides through positron emission tomography (PET) imaging needed investigation. Herein, the chicken CAM tumor models were established, and their feasibility was evaluated for evaluating the imaging properties of radiolabeled peptides using a 68Ga-labeled HER2 affibody.
Methods: Two human breast cancer cell lines were inoculated into chicken CAM and mice, respectively. The tumor-targeting potential and pharmacokinetic profile of a 68Ga-labeled affibody, 68Ga-MZHER, in both tumor models were also determined.
Results: The tumor-formation time in chicken CAM model was shorter than that of mouse model. The uptake values of human epithelial growth factor receptor-2 (HER2)-positive Bcap37 tumors in chicken CAM and mouse models were 5.36±0.26% ID/g and 5.26±0.43% ID/g at 30min postinjection of 68Ga-MZHER, respectively. At the same time points, the uptake values of HER2-negative MDA-MB-231 tumors in the chicken CAM models and mouse models were 1.57±0.15% ID/g and 1.67±0.25% ID/g, respectively. Ex vivo biodistribution confirmed that more radioactivity accumulated in Bcap37 tumors than in MDA-MD-231 tumors in both CAM and mouse models.
Conclusion: In this study, the CAM tumor model was successfully prepared. The chicken CAM model is a novel tool for quickly determining the in vivo properties of radiolabeled peptides targeting biomarkers. It may be beneficial for early monitoring of the therapeutic effect of a new drug through PET imaging with specific peptides.
Background: The forest musk deer, a rare fauna species found in China, is famous for its musk secretion which is used in selected Traditional Chinese medicines. However, over-hunting has led to musk deer becoming an endangered species, and their survival is also greatly challenged by various high incidence and high mortality respiratory and intestinal diseases such as septic pneumonia and enteritis. Accumulating evidence has demonstrated that Akkermannia muciniphila (AKK) is a promising probiotic, and we wondered whether AKK could be used as a food additive in animal breeding programmes to help prevent intestinal diseases.
Methods: We isolated one AKK strain from musk deer feces (AKK-D) using an improved enrichment medium combined with real-time PCR. After confirmation by 16S rRNA gene sequencing, a series of in vitro tests was conducted to evaluate the probiotic effects of AKK-D by assessing its reproductive capability, simulated gastrointestinal fluid tolerance, acid and bile salt resistance, self-aggregation ability, hydrophobicity, antibiotic sensitivity, hemolysis, harmful metabolite production, biofilm formation ability, and bacterial adhesion to gastrointestinal mucosa.
Results: The AKK-D strain has a probiotic function similar to that of the standard strain in humans (AKK-H). An in vivo study found that AKK-D significantly ameliorated symptoms in the enterotoxigenic Escherichia coli (ETEC)-induced murine diarrhea model. AKK-D improved organ damage, inhibited inflammatory responses, and improved intestinal barrier permeability. Additionally, AKK-D promoted the reconstitution and maintenance of the homeostasis of gut microflora, as indicated by the fact that AKK-D-treated mice showed a decrease in Bacteroidetes and an increase in the proportion of other beneficial bacteria like Muribaculaceae, Muribaculum, and unclassified f_Lachnospiaceae compared with the diarrhea model mice.
Conclusion: Taken together, our data show that this novel AKK-D strain might be a potential probiotic for use in musk deer breeding, although further extensive systematic research is still needed.
Background: Artesunate (ASA) acts as an •O2− source through the breakdown of endoperoxide bridges catalyzed by Fe2+, yet its efficacy in ASA-based nanodrugs is limited by poor intracellular delivery.
Methods: ASA-hyaluronic acid (HA) conjugates were formed from hydrophobic ASA and hydrophilic HA by an esterification reaction first, and then self-targeting nanomicelles (NM) were developed using the fact that the amphiphilic conjugates of ASA and HA are capable of self-assembling in aqueous environments.
Results: These ASA-HA NMs utilize CD44 receptor-mediated transcytosis to greatly enhance uptake by breast cancer cells. Subsequently, endogenous Fe2+ from the tumor catalyzes the released ASA to produce highly toxic •O2− radicals to kill tumor cells, although sustained tumor growth inhibition can be achieved via in vivo experiments.
Conclusions: Self-targeting NMs represent a promising strategy for enhancing ASA-based treatments, leveraging clinically approved drugs to expedite drug development and clinical research in oncology.
Background: Nuclear receptor-binding SET domain 2 (NSD2) is a histone methyltransferase, that catalyzes dimethylation of lysine 36 of histone 3 (H3K36me2) and is associated with active transcription of a series of genes. NSD2 is overexpressed in multiple types of solid human tumors and has been proven to be related to unfavorable prognosis in several types of tumors.
Methods: We established a mouse model in which the NSD2 gene was conditionally knocked out in intestinal epithelial cells. We used azoxymethane and dextran sodium sulfate to chemically induce murine colorectal cancer. The development of colorectal tumors were investigated using post-necropsy quantification, immunohistochemistry, and enzyme-linked immunosorbent assay (ELISA).
Results: Compared with wild-type (WT) control mice, NSD2fl/fl-Vil1-Cre mice exhibited significantly decreased tumor numbers, histopathological changes, and cytokine expression in colorectal tumors.
Conclusions: Conditional knockout of NSD2 in intestinal epithelial cells significantly inhibits colorectal cancer progression.
Background: C1QL3 is widely expressed in the brain and is specifically produced by a subset of excitatory neurons. However, its function is still not clear. We established C1ql3-deficient rats to investigate the role of C1QL3 in the brain.
Methods: C1ql3 knockout (KO) rats were generated using CRISPR/Cas9. C1ql3 KO was determined by polymerase chain reaction (PCR), DNA sequencing, and western blotting. Microglia morphology and cytokine expression with or without lipopolysaccharide (LPS) stimulus were analyzed using immunohistochemistry and real-time PCR. The brain structure changes in KO rats were examined using magnetic resonance imaging. Neuronal architecture alteration was analyzed by performing Golgi staining. Behavior was evaluated using the open field test, Morris water maze test, and Y maze test.
Results: C1ql3 KO significantly increased the number of ramified microglia and decreased the number of hypertrophic microglia, whereas C1ql3 KO did not influence the expression of pro-inflammatory factors and anti-inflammatory factors except IL-10. C1ql3 KO brains had more amoeboid microglia types and higher Arg-1 expression compared with the WT rats after LPS stimulation. The brain weights and HPC sizes of C1ql3 KO rats did not differ from WT rats. C1ql3 KO damaged neuronal integrity including neuron dendritic arbors and spine density. C1ql3 KO rats demonstrated an increase in spontaneous activity and an impairment in short working memory.
Conclusions: C1ql3 KO not only interrupts the neuronal integrity but also affects the microglial activation, resulting in hyperactive behavior and impaired short memory in rats, which highlights the role of C1QL3 in the regulation of structure and function of both neuronal and microglial cells.
Background: Under hypoxia, exaggerated compensatory responses may lead to acute mountain sickness. The excessive vasodilatory effect of nitric oxide (NO) can lower the hypoxic pulmonary vasoconstriction (HPV) and peripheral blood pressure. While NO is catalyzed by various nitric oxide synthase (NOS) isoforms, the regulatory roles of these types in the hemodynamics of pulmonary and systemic circulation in living hypoxic animals remain unclear. Therefore, this study aims to investigate the regulatory effects of different NOS isoforms on pulmonary and systemic circulation in hypoxic rats by employing selective NOS inhibitors and continuously monitoring hemodynamic parameters of both pulmonary and systemic circulation.
Methods: Forty healthy male Sprague-Dawley (SD) rats were randomly divided into four groups: Control group (NG-nitro-D-arginine methyl ester, D-NAME), L-NAME group (non-selective NOS inhibitor, NG-nitro-L-arginine methyl ester), AG group (inducible NOS inhibitor group, aminoguanidine), and 7-NI group (neurological NOS inhibitor, 7-nitroindazole). Hemodynamic parameters of rats were monitored for 10min after inhibitor administration and 5min after induction of hypoxia [15% O2, 2200m a. sl., 582mmHg (76.5kPa), Xining, China] using the real-time dynamic monitoring model for pulmonary and systemic circulation hemodynamics in vivo. Serum NO concentrations and blood gas analysis were measured.
Results: Under normoxia, mean arterial pressure and total peripheral vascular resistance were increased, and ascending aortic blood flow and serum NO concentration were decreased in the L-NAME and AG groups. During hypoxia, pulmonary arterial pressure and pulmonary vascular resistance were significantly increased in the L-NAME and AG groups.
Conclusions: This compensatory mechanism activated by inducible NOS and endothelial NOS effectively counteracts the pulmonary hemodynamic changes induced by hypoxic stress. It plays a crucial role in alleviating hypoxia-induced pulmonary arterial hypertension.
Background: Adenoid hypertrophy (AH) is a common pediatric disease that significantly impacts the growth and quality of life of children. However, there is no replicable and valid model for AH.
Methods: An AH rat model was developed via comprehensive allergic sensitization, chronic inflammation induction, and chronic intermittent hypoxia (CIH). The modeling process involved three steps: female Sprague–Dawley rats (aged 4–5weeks) were used for modeling. Allergen sensitization was induced via intraperitoneal administration and intranasal provocation using ovalbumin (OVA); chronic nasal inflammation was induced through intranasal lipopolysaccharide (LPS) administration for sustained nasal irritation; CIH akin to obstructive sleep apnea/hypopnea syndrome was induced using an animal hypoxia chamber. Postmodel establishment, behaviors, and histological changes in nasopharynx-associated lymphoid tissue (NALT) and nasal mucosa were assessed. Arterial blood gas analysis and quantification of serum and tissue levels of (interleukin) IL-4 and IL-13, OVA-specific immunoglobulin E (sIgE), eosinophil cationic protein (ECP), tumor necrosis factor (TNF-α), IL-17, and transforming growth factor (TGF)-β were conducted for assessment. The treatment group received a combination of mometasone furoate and montelukast sodium for a week and then was evaluated.
Results: Rats exhibited notable nasal symptoms and hypoxia after modeling. Histopathological analysis revealed NALT follicle hypertrophy and nasal mucosa inflammatory cell infiltration. Elevated IL-4, IL-13, IL-17, OVA-sIgE, ECP, and TNF-α levels and reduced TGF-β levels were observed in the serum and tissue of model-group rats. After a week of treatment, the treatment group exhibited symptom and inflammatory factor improvement.
Conclusion: The model effectively simulates AH symptoms and pathological changes. But it should be further validated for genetic, immunological, and hormonal backgrounds in the currently used and other strains and species.
Background: The aim was to explore the effect of macrophage polarization and macrophage-to-myofibroblast transition (MMT) in silicosis.
Methods: Male Wistar rats were divided into a control group and a silicosis group developed using a HOPE MED 8050 dynamic automatic dusting system. Murine macrophage MH-S cells were randomly divided into a control group and an SiO2 group. The pathological changes in lung tissue were observed using hematoxylin and eosin (HE) and Van Gieson (VG) staining. The distribution and location of macrophage marker (F4/80), M1 macrophage marker (iNOS), M2 macrophage marker (CD206), and myofibroblast marker (α-smooth muscle actin [α-SMA]) were detected using immunohistochemical and immunofluorescent staining. The expression changes in iNOS, Arg, α-SMA, vimentin, and type I collagen (Col I) were measured using Western blot.
Results: The results of HE and VG staining showed obvious silicon nodule formation and the distribution of thick collagen fibers in the lung tissue of the silicosis group. Macrophage marker F4/80 increased gradually from 8 to 32weeks after exposure to silica. Immunohistochemical and immunofluorescent staining results revealed that there were more iNOS-positive cells and some CD206-positive cells in the lung tissue of the silicosis group at 8weeks. More CD206-positive cells were found in the silicon nodules of the lung tissues in the silicosis group at 32weeks. Western blot analysis showed that the expressions of Inducible nitric oxide synthase and Arg protein in the lung tissues of the silicosis group were upregulated compared with those of the control group. The results of immunofluorescence staining showed the co-expression of F4/80, α-SMA, and Col I, and CD206 and α-SMA were co-expressed in the lung tissue of the silicosis group. The extracted rat alveolar lavage fluid revealed F4/80+α-SMA+, CD206+α-SMA+, and F4/80+α-SMA+Col I+ cells using immunofluorescence staining. Similar results were also found in MH-S cells induced by SiO2.
Conclusions: The development of silicosis is accompanied by macrophage polarization and MMT.
This study developed an animal model with internal and external urethral sphincter insufficiency by bypassing the sphincter without major damage so that the animal under study can return to normal life after the study. There is a need for a reliable, applicable, and reproducible animal model for studying urinary incontinency disease due to incorrect sphincter function. Seven adult male dogs were used for this study. The urethral sphincter was bypassed by inserting a catheter between the bladder neck and the distal sphincter. The animals’ physical condition was closely monitored for 9 weeks, and standard urodynamic and radiologic studies were performed before and 1–2 months after surgery. The animals were killed at 9 weeks after surgery for pathological assessment. Catheter placement caused complete incontinence in the animal, with urodynamic assessments indicating that the animal was unable to control urination and radiological assessments indicating an empty bladder with a residual volume of 50±10cc. Tissue analysis did not show significant histological damage and inflammation. The study shows that by bypassing the urethral sphincter, which is a reliable and reproducible method, an animal model of urinary incontinence can be developed, which can be used in various studies such as assessing the adequacy of artificial sphincter function. The animals under study did not have any permanent defect, so they were able to return to their normal life.
Background: Inhalation exposure is the gold standard when assessing pulmonary toxicity. However, it typically requires substantial amounts of test material. Intratracheal instillation is an alternative administration technique, where the test substance is suspended in a liquid vehicle and deposited into the lung via the trachea. Instillation requires minimal test material, delivers an exact dose deep into the lung, and is less labor-intensive than inhalation exposures. However, one shortcoming is that the procedure may induce short-term inflammation. To minimize this, we tested different modifications of the technique to identify the potential for refinement.
Methods: First, we tested whether previous findings of increased inflammation could be confirmed. Next, we tested whether instillation with a disposable 1mL syringe with ball-tipped steel-needle (Disposable-syringe/steel-needle) induced less inflammation than the use of our standard set-up, a 250µL reusable glass syringe with a disposable plastic catheter (Glass-syringe/plastic-catheter). Finally, we tested if access to pelleted and liquid feed prior to instillation affected inflammation. We evaluated inflammation by neutrophil numbers in bronchoalveolar fluid 24h post-exposure.
Results: Vehicle-instilled mice showed a small increase in neutrophil numbers compared to untreated mice. Neutrophil numbers were slightly elevated in the groups instilled with Disposable-syringe/steel-needle; an interaction with feed type indicated that the increase in neutrophils was more pronounced in combination with feed pellets compared to liquid feed. We found no difference between the feed types when using the Glass-syringe/plastic-catheter combination.
Conclusion: The Glass-syringe/plastic-catheter combination induced the least exposure-related inflammation, confirming this as a preferred instillation procedure.