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1.
Braz. j. biol ; 84: e250936, 2024. graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1345557

ABSTRACT

Abstract This study was carried out to evaluate the effect of Glutamine, as a dipeptide or a free amino acid form, on the progression of burn injuries in rats. Thirty male Wistar rats were burned with a comb metal plate heated in boiling water (98 °C) for three minutes, creating four rectangular full-thickness burn areas separated by three unburned interspaces (zone of stasis) in both dorsum sides. The animals were randomized into three groups (n=10): saline solution (G1-Control) and treated groups that orally received Glutamine as dipeptide (G2-Dip) or free amino acid (G3-FreeAA). Two and seven days after burn injury, lesions were photographed for unburned interspaces necrosis evolution assessment. Seven days after injury, glutathione seric was measured and histopathological analysis was performed. By photographs, there was a significant reduction in necrosis progression in G3-Free-AA between days two and seven. Histopathological analysis at day 7 showed a significantly higher stasis zone without necrosis and a higher number of fibroblasts in G2-Dip and G3-FreeAA compared with G1-Control. Also, glutathione serum dosage was higher in G2-Dip. The plasmatic glutathione levels were higher in the G2-Dip than the G1-Control, and there was a trend to higher levels in G3-FreeAA. The reduction in histological lesions, greater production of fibroblasts, and greater amounts of glutathione may have benefited the evolution of burn necrosis, which showed greater preservation of interspaces.


Resumo Este estudo foi realizado para avaliar o efeito da Glutamina, como um dipeptídeo ou forma de aminoácido livre, na progressão de queimaduras em ratos. Trinta ratos Wistar machos foram queimados com um pente de metal aquecido em água fervente (98 °C) por três minutos, criando quatro áreas retangulares queimadas separadas por três interesespaços não queimados (zona de estase) em ambos os lados do dorso. Os animais foram randomizados em três grupos (n = 10): solução salina (G1-Controle) e grupos tratados que receberam glutamina via oral como dipeptídeo (G2-Dip) ou aminoácido livre (G3-FreeAA). Dois e sete dias após a queimadura, as lesões foram fotografadas para avaliação da evolução da necrose entre os espaços não queimados. Sete dias após a lesão, foi dosada a glutationa sérica e realizada análise histopatológica. Pelas fotografias, houve uma redução significativa na progressão da necrose no G3-Free-AA entre os dias dois e sete. A análise histopatológica no dia 7 mostrou uma zona de estase significativamente maior sem necrose e número mais elevado de fibroblastos em G2-Dip e G3-FreeAA em comparação com G1-Controle. Os níveis plasmáticos de glutationa foram maiores no G2-Dip em relação ao G1-Controle, e houve tendência a níveis mais elevados no G3-FreeAA. A redução das lesões histológicas, maior produção de fibroblastos, maior quantidade de glutationa podem ter beneficiado a evolução da necrose da queimadura, que mostrou maior preservação dos interespaços.


Subject(s)
Animals , Male , Rats , Burns/drug therapy , Glutamine , Rats, Wistar , Dipeptides , Disease Models, Animal , Amino Acids
2.
Braz. j. biol ; 84: e252575, 2024. tab
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1355869

ABSTRACT

Abstract Increased anxiety and depressive symptoms have reported to be its association with long term illness. Because of having unwanted effects of newly available drugs, patients administering anxiolytic drugs usually discontinue the treatment before they are completely recovered. Therefore, there is a serious need to develop new anxiolytic drugs. The anxiolytic effect of hydro-alcoholic extract of Agaricus blazei in animal models was assessed. 24 male mice (Mus musculus genus) were included in the study. Four groups were prepared and each group contained six animals. The groups were vehicle control, positive control (diazepam 1.0 mg/kg, i.p.) as well as two treatment groups receiving Agaricus blazei hydro-alcoholic extract at a dose of 136.50 mg/kg and 273.0 mg/kg orally. The Marble burying test, Nestlet shredding test and Light and Dark box test used to assess anxiolytic activity. Mice administered with diazepam 1.0 mg/kg, i.p. while hydro-alcoholic extract of AbM (136.50 and 273.0 mg/kg, respectively) was administered via oral route which exhibited marked reduction in number of marbles-burying as compared to vehicle control group. Mice administered with diazepam 1.0 mg/kg, i.p. and Oral administration of hydro-alcoholic extract of AbM (136.50 and 273.0 mg/kg, respectively) exhibited significant decrease in nestlet shredding in comparison to vehicle control group. The oral administration of hydro-alcoholic extract at a dose of 136.5mg/kg and 273mg/kg showed elevation in time spent in light box and was comparable to standard treated group while time spent by mice following oral administration of hydro-alcoholic extract of Agaricus blazei at a dose of 273.0 mg/kg also showed elevation and was found to be more near to standard treated group (diazepam 1 mg/kg, i.p.).


Resumo O aumento da ansiedade e dos sintomas depressivos têm relatado sua associação com doenças de longa duração. Por causa dos efeitos indesejáveis dos novos medicamentos disponíveis, os pacientes que administram medicamentos ansiolíticos geralmente interrompem o tratamento antes de estarem completamente recuperados. Portanto, há uma necessidade séria de desenvolver novos medicamentos ansiolíticos. Foi avaliado o efeito ansiolítico do extrato hidroalcoólico de Agaricus blazei em modelos animais. Vinte e quatro camundongos machos (gênero Mus musculus) foram incluídos no estudo. Quatro grupos foram preparados, e cada grupo continha seis animais. Os grupos foram controle de veículo, controle positivo (diazepam 1,0 mg/kg, i.p.), bem como dois grupos de tratamento recebendo extrato hidroalcoólico de Agaricus blazei na dose de 136,50 mg/kg e 273,0 mg/kg por via oral. O teste de enterrar Marble, o teste de retalhamento Nestlet e o teste de caixa clara e escura são usados ​​para avaliar a atividade ansiolítica. Camundongos foram administrados com diazepam 1,0 mg/kg, i.p., enquanto o extrato hidroalcoólico de AbM (136,50 e 273,0 mg/kg, respectivamente) foi administrado por via oral, que exibiu redução acentuada no número de mármores enterrados em comparação com o grupo de controle de veículo. Camundongos administrados com diazepam 1,0 mg/kg, i.p. e a administração oral de extrato hidroalcoólico de AbM (136,50 e 273,0 mg/kg, respectivamente) exibiu diminuição significativa na trituração de ninhos em comparação ao grupo de controle de veículo. A administração oral de extrato hidroalcoólico na dose de 136,5mg/kg e 273mg/kg mostrou elevação no tempo gasto na caixa de luz e foi comparável ao grupo tratado padrão, enquanto o tempo gasto por camundongos após a administração oral de extrato hidroalcoólico de Agaricus blazei na dose de 273,0 mg/kg também mostrou elevação e foi mais próximo do grupo tratado padrão (diazepam 1 mg/kg, ip).


Subject(s)
Animals , Male , Rabbits , Agaricus , Exploratory Behavior , Disease Models, Animal
3.
Braz. j. biol ; 84: e253616, 2024. tab, graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1355880

ABSTRACT

Abstract This study evaluated the effect of the volatile oil of Alpinia zerumbet (VOAz) on caveolin-1 gene expression and muscular fibrosis. The rats were immobilized to induce fibrosis of the gastrocnemius muscle, and they were treated with VOAz. Collagen quality was assessed by histology and the expression of the caveolin-1 (CAV-1) gene was evaluated using qPCR. Histomorphological analysis indicated a significant reduction in the perimeter, width, and intensity of collagen in the treated groups, thus showing that the oil was effective in regulating the quality of collagen at the three concentrations. The results of expression levels suggested a decrease in the lesioned group and in two treatment groups (0.0115 µg/g and 0.009 µg/g). However, with the lowest concentration (0.0065 µg/g), no significant difference was observed, with levels similar to those found in healthy tissue. Therefore, the results showed that VOAz has the potential to be a non-invasive and low-cost alternative to aid in the treatment of muscular fibrosis.


Resumo Este estudo avaliou o efeito do óleo volátil de Alpinia zerumbet (OVAz) na expressão do gene da caveolina-1 e na fibrose muscular. Os ratos foram imobilizados para induzir a fibrose do músculo gastrocnêmio, e foram tratados com OVAz. A qualidade do colágeno foi avaliada com histologia e à expressão do gene caveolina-1 (CAV-1) foi avaliada usando qPCR. A análise histomorfológica indicou uma redução significativa no perímetro, largura e intensidade do colágeno nos grupos tratados. Os resultados dos níveis de expressão sugeriram diminuição nos grupos de lesão e em dois grupos de tratamento (0,0115 µg/g e 0,009 µg/g). No entanto, com a menor concentração (0,0065 µg/g), não foi observada diferença significativa, apresentando níveis semelhantes aos encontrados em tecido saudável. O uso do OVAz foi eficaz para reverter as alterações do colágeno causadas pela fibrose, e sua menor concentração apresentou uma possível tendência de aumento na expressão do CAV-1. Portanto, os resultados mostraram que o OVAz tem potencial para ser uma alternativa não invasiva e de baixo custo para auxiliar no tratamento da fibrose muscular.


Subject(s)
Animals , Rats , Oils, Volatile/pharmacology , Collagen/metabolism , Alpinia/chemistry , Caveolin 1/metabolism , Muscles/drug effects , Fibrosis , Plant Oils/pharmacology , Brazil , Rats, Wistar , Disease Models, Animal , Muscles/pathology
4.
J Lipid Res ; 63(3): 100174, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35101425

ABSTRACT

Antisense oligonucleotides (ASOs) against Ldl receptor (Ldlr-ASO) represent a promising strategy to promote hypercholesterolemic atherosclerosis in animal models without the need for complex breeding strategies. Here, we sought to characterize and contrast atherosclerosis in mice given Ldlr-ASO with those bearing genetic Ldlr deficiency. To promote atherosclerosis, male and female C57Bl6/J mice were either given weekly injections of Ldlr-ASO (5 mg/kg once per week) or genetically deficient in Ldlr (Ldlr-/-). Mice consumed either standard rodent chow or a diet high in saturated fat and sucrose with 0.15% added cholesterol for 16 weeks. While both models of Ldlr deficiency promoted hypercholesterolemia, Ldlr-/- mice exhibited nearly 2-fold higher cholesterol levels than Ldlr-ASO mice, reflected by increased VLDL and LDL levels. Consistent with this, the en face atherosclerotic lesion area was 3-fold and 3.6-fold greater in male and female mice with genetic Ldlr deficiency, respectively, as compared with the modest atherosclerosis observed following Ldlr-ASO treatment. Aortic sinus lesion sizes, fibrosis, smooth muscle actin, and necrotic core areas were also larger in Ldlr-/- mice, suggesting a more advanced phenotype. Despite a more modest effect on hypercholesterolemia, Ldlr-ASO induced greater hepatic inflammatory gene expression, macrophage accumulation, and histological lobular inflammation than was observed in Ldlr-/- mice. We conclude Ldlr-ASO is a promising tool for the generation of complex rodent models with which to study atherosclerosis but does not promote comparable levels of hypercholesterolemia or atherosclerosis as Ldlr-/- mice and increases hepatic inflammation. Thus, genetic Ldlr deficiency may be a superior model, depending on the proposed use.


Subject(s)
Atherosclerosis , Hypercholesterolemia , Animals , Atherosclerosis/metabolism , Cholesterol , Disease Models, Animal , Female , Hypercholesterolemia/genetics , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Pharmaceutical Preparations , Receptors, LDL/genetics
5.
Elife ; 112022 May 10.
Article in English | MEDLINE | ID: mdl-35535852

ABSTRACT

Pitt-Hopkins syndrome (PTHS) is a neurodevelopmental disorder caused by monoallelic mutation or deletion in the transcription factor 4 (TCF4) gene. Individuals with PTHS typically present in the first year of life with developmental delay and exhibit intellectual disability, lack of speech, and motor incoordination. There are no effective treatments available for PTHS, but the root cause of the disorder, TCF4 haploinsufficiency, suggests that it could be treated by normalizing TCF4 gene expression. Here, we performed proof-of-concept viral gene therapy experiments using a conditional Tcf4 mouse model of PTHS and found that postnatally reinstating Tcf4 expression in neurons improved anxiety-like behavior, activity levels, innate behaviors, and memory. Postnatal reinstatement also partially corrected EEG abnormalities, which we characterized here for the first time, and the expression of key TCF4-regulated genes. Our results support a genetic normalization approach as a treatment strategy for PTHS, and possibly other TCF4-linked disorders.


Subject(s)
Intellectual Disability , Transcription Factor 4/metabolism , Animals , Disease Models, Animal , Facies , Hyperventilation , Intellectual Disability/genetics , Intellectual Disability/metabolism , Mice , Phenotype , Transcription Factor 4/genetics
6.
PLoS One ; 17(5): e0268223, 2022.
Article in English | MEDLINE | ID: mdl-35536857

ABSTRACT

BACKGROUND: Established MRI and emerging X-ray contrast agents for non-invasive imaging of articular cartilage rely on non-selective electrostatic interactions with negatively charged proteoglycans. These contrast agents have limited prognostic utility in diseases such as osteoarthritis (OA) due to the characteristic high turnover of proteoglycans. To overcome this limitation, we developed a radiocontrast agent that targets the type II collagen macromolecule in cartilage and used it to monitor disease progression in a murine model of OA. METHODS: To confer radiopacity to cartilage contrast agents, the naturally occurring tyrosine derivative 3,5-diiodo-L-tyrosine (DIT) was introduced into a selective peptide for type II collagen. Synthetic DIT peptide derivatives were synthesised by Fmoc-based solid-phase peptide synthesis and binding to ex vivo mouse tibial cartilage evaluated by high-resolution micro-CT. Di-Iodotyrosinated Peptide Imaging of Cartilage (DIPIC) was performed ex vivo and in vivo 4, 8 and 12 weeks in mice after induction of OA by destabilisation of the medial meniscus (DMM). Finally, human osteochondral plugs were imaged ex vivo using DIPIC. RESULTS: Fifteen DIT peptides were synthesised and tested, yielding seven leads with varying cartilage binding strengths. DIPIC visualised ex vivo murine articular cartilage comparably to the ex vivo contrast agent phosphotungstic acid. Intra-articular injection of contrast agent followed by in vivo DIPIC enabled delineation of damaged murine articular cartilage. Finally, the translational potential of the contrast agent was confirmed by visualisation of ex vivo human cartilage explants. CONCLUSION: DIPIC has reduction and refinement implications in OA animal research and potential clinical translation to imaging human disease.


Subject(s)
Cartilage, Articular , Osteoarthritis , Animals , Cartilage, Articular/diagnostic imaging , Cartilage, Articular/metabolism , Collagen Type II/metabolism , Contrast Media/metabolism , Disease Models, Animal , Mice , Osteoarthritis/diagnostic imaging , Osteoarthritis/metabolism , Peptides/metabolism , Proteoglycans/metabolism , X-Ray Microtomography/methods
7.
Sci Data ; 9(1): 197, 2022 05 10.
Article in English | MEDLINE | ID: mdl-35538082

ABSTRACT

The gut microbiota is associated with the health and longevity of the host. A few methods, such as fecal microbiota transplantation and oral administration of probiotics, have been applied to alter the gut microbiome and promote healthy aging. The changes in host microbiomes still remain poorly understood. Here, we characterized both the changes in gut microbial communities and their functional potential derived from colon samples in mouse models during aging. We achieved this through four procedures including co-housing, serum injection, parabiosis, and oral administration of Akkermansia muciniphila as probiotics using bacterial 16 S rRNA sequencing and shotgun metagenomic sequencing. The dataset comprised 16 S rRNA sequencing (36,249,200 paired-end reads, 107 sequencing data) and metagenomic sequencing data (307,194,369 paired-end reads, 109 sequencing data), characterizing the taxonomy of bacterial communities and their functional potential during aging and rejuvenation. The generated data expand the resources of the gut microbiome related to aging and rejuvenation and provide a useful dataset for research on developing therapeutic strategies to achieve healthy active aging.


Subject(s)
Aging , Gastrointestinal Microbiome , RNA, Ribosomal, 16S , Aging/genetics , Animals , Disease Models, Animal , Gastrointestinal Microbiome/genetics , Metagenomics , Mice , RNA, Ribosomal, 16S/genetics , Rejuvenation
8.
J Transl Med ; 20(1): 206, 2022 May 10.
Article in English | MEDLINE | ID: mdl-35538576

ABSTRACT

The establishing of the first cancer models created a new perspective on the identification and evaluation of new anti-cancer therapies in preclinical studies. Patient-derived xenograft models are created by tumor tissue engraftment. These models accurately represent the biology and heterogeneity of different cancers and recapitulate tumor microenvironment. These features have made it a reliable model along with the development of humanized models. Therefore, they are used in many studies, such as the development of anti-cancer drugs, co-clinical trials, personalized medicine, immunotherapy, and PDX biobanks. This review summarizes patient-derived xenograft models development procedures, drug development applications in various cancers, challenges and limitations.


Subject(s)
Neoplasms , Precision Medicine , Animals , Disease Models, Animal , Heterografts , Humans , Neoplasms/pathology , Precision Medicine/methods , Tumor Microenvironment , Xenograft Model Antitumor Assays
9.
Front Immunol ; 13: 695576, 2022.
Article in English | MEDLINE | ID: mdl-35514976

ABSTRACT

Aberrant innate immune responses to the gut microbiota are causally involved in the pathogenesis of inflammatory bowel diseases (IBD). The exact triggers and main signaling pathways activating innate immune cells and how they modulate adaptive immunity in IBD is still not completely understood. Here, we report that the PI3K/PTEN signaling pathway in dendritic cells enhances IL-6 production in a model of DSS-induced colitis. This results in exacerbated Th1 cell responses and increased mortality in DC-specific PTEN knockout (PTENΔDC) animals. Depletion of the gut microbiota using antibiotics as well as blocking IL-6R signaling rescued mortality in PTENΔDC mice, whereas adoptive transfer of Flt3L-derived PTEN-/- DCs into WT recipients exacerbated DSS-induced colitis and increased mortality. Taken together, we show that the PI3K signaling pathway in dendritic cells contributes to disease pathology by promoting IL-6 mediated Th1 responses.


Subject(s)
Colitis , Inflammatory Bowel Diseases , Animals , Dendritic Cells , Dextran Sulfate/adverse effects , Disease Models, Animal , Interleukin-6/metabolism , Mice , Mice, Inbred C57BL , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction
10.
Front Immunol ; 13: 860311, 2022.
Article in English | MEDLINE | ID: mdl-35514982

ABSTRACT

Primary biliary cholangitis (PBC), an organ-specific autoimmune disease, is characterized by injury to small bile ducts, inflammatory cell infiltrates within the liver, progressive cholestasis, and in some cases, cirrhosis with unclear pathogenesis. We aimed to clarify the importance role of hepatic immunce cells in the pathogenesis of human and experimental PBC.The dominant-negative TGFß receptor type II transgenic (dnTGFßRII) mice, a well-studied and established murine model of PBC were used to identify changes of immune cells, especially the pathogenic CD8+ T cells. The high-throughput single-cell RNA sequencing technology were applied and found functional heterogeneity among the hepatic CD8+ T cells subsets in dnTGFßRII mice. CD8+ T cells were confirmed the key cells leading to the pathogenesis of PBC in dnTGFßRII mice, and identified the terminally differentiated CD8αα T cells and CD8αß T cell subsets in the liver of dnTGFßRII mice. While terminally differentiated CD8αα T cells have higher cytokine production ability and cytotoxicity, the terminally differentiated CD8αß T cells retain their proliferative profile. Our work suggests that there are developmental and differentiated trajectories of pathogenic CD8+ T cell subsets in the pathogenesis of PBC. A further clarification of their roles would be helpful to our understanding of the pathogenesis of PBC and may potentially lead to identifying novel therapeutic modalities.


Subject(s)
Autoimmune Diseases , Liver Cirrhosis, Biliary , Animals , CD8-Positive T-Lymphocytes , Disease Models, Animal , Mice
11.
Mol Imaging ; 2022: 9589820, 2022.
Article in English | MEDLINE | ID: mdl-35517713

ABSTRACT

EGFR (epidermal growth factor receptor) is overexpressed in a variety of human cancers (including squamous cell carcinoma of head and neck, colon cancer, and some breast cancers) and therefore is regarded as an ideal target for cancer therapy or imaging purposes. In the current study, we produced a scFv-based near-infrared probe (called cet.Hum.scFv-IRDye-800CW) and evaluated its ability in recognizing and imaging of EGFR-overexpressing tumors in a mouse model. Like the molecular probe consisting of its parental antibody (cetuximab, an FDA-approved monoclonal antibody) and IRD800CW, cet.Hum.scFv-IRDye-800CW was able to recognize EGFR-overexpressing tumors in mice. cet.Hum.scFv-IRDye-800CW was found to be superior to the cetuximab-based probe in imaging of mouse tumors. The tumor-to-background ratio and blood clearance rate were higher when cet.Hum.scFv-IRDye-800CW was used as an imaging probe.


Subject(s)
ErbB Receptors , Immunoconjugates , Animals , Cell Line, Tumor , Cetuximab , Disease Models, Animal , ErbB Receptors/metabolism , Heterografts , Humans , Mice , Mice, Nude , Optical Imaging/methods
12.
Drug Des Devel Ther ; 16: 1273-1287, 2022.
Article in English | MEDLINE | ID: mdl-35517984

ABSTRACT

Background: Oxidative stress and inflammatory reaction play critical roles in acute myocardial infarction (AMI). Isoliquiritigenin (ISL), a flavonoid monomer extracted from licorice, has been found to have antioxidant and anti-inflammatory effects in cancer studies. Here, we tested the effect and underlying mechanisms of ISL on ischemia-induced myocardial injury in a mouse AMI model. Methods: Adult C57BL/6 mice were pre-treated by intraperitoneal injection of ISL and/or a specific nuclear factor E2-related factor 2 (Nrf2) inhibitor ML385 for 3 days, respectively. Then, the AMI model was established by ligating the anterior descending branch of the left coronary artery. Myocardial oxidative stress status, inflammatory response, cardiac function and infarction size were assessed after 7th day of surgery. Results: Compared with sham group, the reactive oxygen species (ROS) and malondialdehyde (MDA) level in AMI group were significantly increased. However, the superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) level were dramatically decreased. ISL treatment significantly reduced the myocardial infarction area, improved cardiac function, inhibited the production of ROS and MDA and reduced the consumption of SOD and GSH-Px. Interestingly, ISL could significantly increase nuclear Nrf2 and cytosolic heme oxygenase 1 (HO-1) level in the infarcted myocardium and reduce the oxidative stress after AMI. Also, ISL treatment dramatically inhibited the activation of myocardial NF-κB pathway and reduced the expression of pro-inflammatory factors in the AMI group. However, the administration of ML385 not only suppressed the Nrf2/HO-1 activation, the anti-oxidant and anti-inflammatory effects induced by ISL, but also attenuated the beneficial role of ISL on reducing infarct size and improving cardiac function in the mouse with AMI. Conclusion: The results suggested that activation of Nrf2/HO-1 pathway has an essential role in ISL-induced cardiac protection by alleviating myocardial oxidative stress and inflammation response in mice with AMI.


Subject(s)
Myocardial Infarction , NF-E2-Related Factor 2 , Animals , Anti-Inflammatory Agents/pharmacology , Antioxidants/metabolism , Antioxidants/pharmacology , Chalcones , Disease Models, Animal , Glutathione Peroxidase/metabolism , Heme Oxygenase-1/metabolism , Mice , Mice, Inbred C57BL , Myocardial Infarction/drug therapy , Myocardial Infarction/prevention & control , NF-E2-Related Factor 2/metabolism , Oxidative Stress , Reactive Oxygen Species , Superoxide Dismutase/metabolism
13.
Nat Neurosci ; 25(5): 596-606, 2022 May.
Article in English | MEDLINE | ID: mdl-35501379

ABSTRACT

Activity-dependent myelination can fine-tune neural network dynamics. Conversely, aberrant neuronal activity, as occurs in disorders of recurrent seizures (epilepsy), could promote maladaptive myelination, contributing to pathogenesis. In this study, we tested the hypothesis that activity-dependent myelination resulting from absence seizures, which manifest as frequent behavioral arrests with generalized electroencephalography (EEG) spike-wave discharges, promote thalamocortical network hypersynchrony and contribute to epilepsy progression. We found increased oligodendrogenesis and myelination specifically within the seizure network in two models of generalized epilepsy with absence seizures (Wag/Rij rats and Scn8a+/mut mice), evident only after epilepsy onset. Aberrant myelination was prevented by pharmacological seizure inhibition in Wag/Rij rats. Blocking activity-dependent myelination decreased seizure burden over time and reduced ictal synchrony as assessed by EEG coherence. These findings indicate that activity-dependent myelination driven by absence seizures contributes to epilepsy progression; maladaptive myelination may be pathogenic in some forms of epilepsy and other neurological diseases.


Subject(s)
Epilepsy, Absence , Epilepsy, Generalized , Animals , Disease Models, Animal , Electroencephalography , Epilepsy, Generalized/genetics , Mice , NAV1.6 Voltage-Gated Sodium Channel , Rats , Rats, Wistar , Seizures
14.
PLoS One ; 17(5): e0263546, 2022.
Article in English | MEDLINE | ID: mdl-35507596

ABSTRACT

Model organisms mimicking the pathogenesis of human diseases are useful for identifying pathogenic mechanisms and testing therapeutic efficacy of compounds targeting them. Models of Alzheimer's disease (AD) and related dementias (ADRD) aim to reproduce the brain pathology associated with these neurodegenerative disorders. Transgenic models, which involve random insertion of disease-causing genes under the control of artificial promoters, are efficient means of doing so. There are confounding factors associated with transgenic approaches, however, including target gene overexpression, dysregulation of endogenous gene expression at transgenes' integration sites, and limitations in mimicking loss-of-function mechanisms. Furthermore, the choice of species is important, and there are anatomical, physiological, and cognitive reasons for favoring the rat over the mouse, which has been the standard for models of neurodegeneration and dementia. We report an initial assessment of the spatial learning, reversal, and sequencing task capabilities of knock-in (KI) Long-Evans rats with humanizing mutations in the Aß-coding region of App, which encodes amyloid precursor protein (Apph/h rats), using the IntelliCage, an automated operant social home cage system, at 6-8 weeks of age, then again at 4-5 months of age. These rats were previously generated as control organisms for studies on neurodegeneration involving other knock-in rat models from our lab. Apph/h rats of either sex can acquire place learning and reversal tasks. They can also acquire a diagonal sequencing task by 6-8 weeks of age, but not a more advanced serial reversal task involving alternating diagonals, even by 4-5 months of age. Thus, longitudinal behavioral analysis with the IntelliCage system can be useful to determine, in follow-up studies, whether KI rat models of Familial AD (FAD), sporadic late onset AD (LOAD), and of ADRD develop aging-dependent learning and memory deficits.


Subject(s)
Alzheimer Disease , Mobile Applications , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Amyloid beta-Protein Precursor/genetics , Amyloid beta-Protein Precursor/metabolism , Animals , Disease Models, Animal , Mice, Transgenic , Mutation , Rats , Rats, Long-Evans , Reversal Learning
15.
Neuron ; 110(9): 1433-1435, 2022 05 04.
Article in English | MEDLINE | ID: mdl-35512633

ABSTRACT

Genetic and environmental factors during development are involved in autism, and in this issue of Neuron Krüttner et al. (2022) find environment may play a more acute role in modulating autism behavior in a Shank3 exon 21 deletion mutant mouse (Shank3ΔC/ΔC). The authors explore the underlying circuit mechanisms in detail.


Subject(s)
Autism Spectrum Disorder , Autistic Disorder , Animals , Autism Spectrum Disorder/genetics , Autistic Disorder/genetics , Disease Models, Animal , Mice , Microfilament Proteins , Nerve Tissue Proteins/genetics
16.
BMC Ophthalmol ; 22(1): 206, 2022 May 06.
Article in English | MEDLINE | ID: mdl-35524186

ABSTRACT

BACKGROUND: This study aims to investigate the effect of the glucagon-like peptide-1 (GLP-1) receptor agonist (GLP-1RA) liraglutide on retinal pathological findings as compared with insulin and hydralazine using an animal model of type 2 diabetes with obesity, hypertension, and hyperlipidemia. METHODS: Male spontaneously diabetic Torii (SDT) fatty rats at 8 weeks of age were randomly assigned to three groups: the liraglutide group (SDT-lira, n = 6) received a subcutaneous injection of liraglutide from the age of 8 to 16 weeks, the SDT-ins-hyd group (n = 6) was provided both insulin against hyperglycemia and hydralazine against hypertension to match levels of both blood glucose and blood pressure to those of the liraglutide group, and the control group of SDT fatty rats (SDT-vehicle, n = 7) and a nondiabetic control group of Sprague-Dawley rats (SD, n = 7) were injected with vehicle only. Both eyeballs of all groups were collected at the age of 16 weeks. RESULTS: Retinal thickness, which was found in the SDT-vehicle group, was significantly prevented to similar levels in both the SDT-lira and SDT-ins-hyd groups. Immunohistological analysis revealed that GLP-1 receptor was not expressed in the retina of all rats. The ocular protein expression of monocyte chemoattractant protein-1, which causes a proinflammatory situation, was significantly upregulated in all SDT fatty rats as compared to SD rats, but the expression levels were similar between all SDT fatty rats. With regard to neovascularization in the eyes, there were no significant differences in protein expressions of vascular endothelial growth factor, CD31, or endothelial nitric oxide synthase in all rats. CONCLUSIONS: The present study indicates that liraglutide prevents retinal thickening, dependent on blood glucose and blood pressure levels in SDT fatty rats without ocular neovascularization. However, the effects did not improve the ocular proinflammatory state.


Subject(s)
Diabetes Mellitus, Type 2 , Hypertension , Insulins , Animals , Blood Glucose/metabolism , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Disease Models, Animal , Glucagon-Like Peptide-1 Receptor , Humans , Hydralazine , Liraglutide/pharmacology , Liraglutide/therapeutic use , Male , Rats , Rats, Sprague-Dawley , Vascular Endothelial Growth Factor A/metabolism
17.
Iran J Allergy Asthma Immunol ; 21(1): 65-72, 2022 Feb 06.
Article in English | MEDLINE | ID: mdl-35524379

ABSTRACT

Asthma is considered a complex disease of the respiratory system that is characterized by bronchoconstriction, airway inflammation, cough, dyspnea, and wheezing. Allergic reactions are the main reason behind asthma which is known as an important health problem with a high rate of morbidity and mortality in patients with respiratory diseases. Liquorice, the root of Glycyrrhiza, is primarily effective for asthma which is widely used in herbal medicine. In the present study, we designed nano-particles that carry Glycyrrhizic acid as the effective component of Liquorice. After Poly (D,L-lactide-co-glycolic acid) PLGA nanoparticle preparation and Glycyrrhizic acid loading, the morphology of the nanoparticle, the electric charge distribution, and drug-releasing ability were studied. Then the effect of Glycyrrhizic acid-PLGA on the animal model of allergic asthma was investigated. Glycyrrhizic acid-nanoparticle had a mean±SD size of 350±50 nm. about 67% of the effective component was released after 10 h. The interleukin (IL)-4, IL-5, IL-13, and IL-25 levels and the Muc5ac mRNA expression were decreased in the Glycyrrhizic acid-PLGA treated group. In addition, a significant decline was observed in goblet cell hyperplasia, mucus hyper-secretion, and eosinophilic inflammation around bronchi and vessels of the nano-drug treated group, compared with the asthmatic group. We found that Glycyrrhizic acid-PLGA nanoparticle had an anti-asthma effect which may be used as a new drug to cure asthma. It can prevent bronchial obstruction, breathlessness, and asthma attacks.


Subject(s)
Anti-Asthmatic Agents , Asthma , Hypersensitivity , Animals , Anti-Asthmatic Agents/therapeutic use , Asthma/drug therapy , Asthma/metabolism , Disease Models, Animal , Glycyrrhizic Acid/therapeutic use , Humans , Hypersensitivity/drug therapy , Inflammation/drug therapy
18.
J Neuroinflammation ; 19(1): 108, 2022 May 07.
Article in English | MEDLINE | ID: mdl-35525962

ABSTRACT

INTRODUCTION: The mechanism by which adamantinomatous craniopharyngioma (ACP) damages the hypothalamus is still unclear. Cyst fluid rich in lipids and inflammatory factors is a characteristic pathological manifestation of ACP and may play a very important role in hypothalamic injury caused by tumors. OBJECTIVE: The objective of this study was to construct a reliable animal model of ACP cyst fluid-induced hypothalamic injury and explore the specific mechanism of hypothalamic injury caused by cyst fluid. METHODS: An animal model was established by injecting human ACP cyst fluid into the bilateral hypothalamus of mice. ScRNA-seq was performed on the mice hypothalamus and on an ACP sample to obtain a complete gene expression profile for analysis. Data verification was performed through pathological means. RESULTS: ACP cystic fluid caused growth retardation and an increased obesity index in mice, affected the expression of the Npy, Fgfr2, Rnpc3, Sst, and Pcsk1n genes that regulate growth and energy metabolism in hypothalamic neurons, and enhanced the cellular interaction of Agrp-Mc3r. ACP cystic fluid significantly caused inflammatory activation of hypothalamic microglia. The cellular interaction of CD74-APP is significantly strengthened between inflammatory activated microglia and hypothalamic neurons. Beta-amyloid, a marker of neurodegenerative diseases, was deposited in the ACP tumor tissues and in the hypothalamus of mice injected with ACP cyst fluid. CONCLUSION: In this study, a novel animal model of ACP cystic fluid-hypothalamic injury was established. For the first time, it was found that ACP cystic fluid can trigger inflammatory activation of microglia to damage the hypothalamus, which may be related to the upregulation of the CD74-APP interaction and deposition of ß-amyloid, implying that there may be a similar mechanism between ACP cystic fluid damage to the hypothalamus and neurodegenerative diseases.


Subject(s)
Craniopharyngioma , Pituitary Neoplasms , Amyloid beta-Peptides/metabolism , Animals , Craniopharyngioma/genetics , Craniopharyngioma/metabolism , Craniopharyngioma/pathology , Cyst Fluid/metabolism , Disease Models, Animal , Hypothalamus/metabolism , Mice , Microglia/metabolism , Neurons/metabolism , Pituitary Neoplasms/genetics , Pituitary Neoplasms/metabolism , Pituitary Neoplasms/pathology
19.
J Nanobiotechnology ; 20(1): 218, 2022 May 07.
Article in English | MEDLINE | ID: mdl-35525963

ABSTRACT

Acute myocardial infarction (MI) induces a sterile inflammatory response that may result in poor cardiac remodeling and dysfunction. Despite the progress in anti-cytokine biologics, anti-inflammation therapy of MI remains unsatisfactory, due largely to the lack of targeting and the complexity of cytokine interactions. Based on the nature of inflammatory chemotaxis and the cytokine-binding properties of neutrophils, we fabricated biomimetic nanoparticles for targeted and broad-spectrum anti-inflammation therapy of MI. By fusing neutrophil membranes with conventional liposomes, we fabricated biomimetic liposomes (Neu-LPs) that inherited the surface antigens of the source cells, making them ideal decoys of neutrophil-targeted biological molecules. Based on their abundant chemokine and cytokine membrane receptors, Neu-LPs targeted infarcted hearts, neutralized proinflammatory cytokines, and thus suppressed intense inflammation and regulated the immune microenvironment. Consequently, Neu-LPs showed significant therapeutic efficacy by providing cardiac protection and promoting angiogenesis in a mouse model of myocardial ischemia-reperfusion. Therefore, Neu-LPs have high clinical translation potential and could be developed as an anti-inflammatory agent to remove broad-spectrum inflammatory cytokines during MI and other neutrophil-involved diseases.


Subject(s)
Cytokines , Neutrophils , Animals , Anti-Inflammatory Agents , Biomimetics , Disease Models, Animal , Lipopolysaccharides , Liposomes , Mice
20.
Mol Neurodegener ; 17(1): 34, 2022 May 07.
Article in English | MEDLINE | ID: mdl-35526004

ABSTRACT

BACKGROUND: The dietary consumption of cuprizone - a copper chelator - has long been known to induce demyelination of specific brain structures and is widely used as model of multiple sclerosis. Despite the extensive use of cuprizone, the mechanism by which it induces demyelination are still unknown. With this review we provide an updated understanding of this model, by showcasing two distinct yet overlapping modes of action for cuprizone-induced demyelination; 1) damage originating from within the oligodendrocyte, caused by mitochondrial dysfunction or reduced myelin protein synthesis. We term this mode of action 'intrinsic cell damage'. And 2) damage to the oligodendrocyte exerted by inflammatory molecules, brain resident cells, such as oligodendrocytes, astrocytes, and microglia or peripheral immune cells - neutrophils or T-cells. We term this mode of action 'extrinsic cellular damage'. Lastly, we summarize recent developments in research on different forms of cell death induced by cuprizone, which could add valuable insights into the mechanisms of cuprizone toxicity. With this review we hope to provide a modern understanding of cuprizone-induced demyelination to understand the causes behind the demyelination in MS.


Subject(s)
Cuprizone , Demyelinating Diseases , Animals , Astrocytes/metabolism , Cuprizone/metabolism , Cuprizone/toxicity , Demyelinating Diseases/chemically induced , Demyelinating Diseases/metabolism , Disease Models, Animal , Mice , Mice, Inbred C57BL , Microglia/metabolism , Myelin Sheath , Oligodendroglia/metabolism
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