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1.
iScience ; 27(6): 109974, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38832028

RESUMO

Prader-Willi syndrome (PWS) is a genetic disorder characterized by behavioral disturbances, hyperphagia, and intellectual disability. Several surveys indicate that PWS is also associated with cardiac abnormalities, possibly contributing to a high incidence of sudden death. However, the pathological mechanisms underlying cardiac dysfunction in PWS remain unclear. In this study, we found that deficiency in necdin, an intronless gene within PWS region, led to heart systolic and diastolic dysfunction in mice. Through yeast two-hybrid screening, we identified an interaction between necdin and non-muscle myosin regulatory light chain 12a/b (MYL12 A/B). We further showed that necdin stabilized MYL12 A/B via SGT1-heat shock protein 90 (HSP90) chaperone machinery. The zebrafish lacking the MYL12 A/B analog, MYL12.1, exhibited impaired heart function, while cardiac-specific overexpression of MYL12A normalized the heart dysfunction in necdin-deficient mice. Our findings revealed necdin dysfunction as a contributing factor to cardiomyopathy in PWS patients and emphasized the importance of HSP90 chaperone machinery and non-muscle myosin in heart fitness.

2.
J Cancer Res Clin Oncol ; 150(5): 231, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38703241

RESUMO

PURPOSE: Acute myeloid leukemia (AML) is a refractory hematologic malignancy that poses a serious threat to human health. Exploring alternative therapeutic strategies capable of inducing alternative modes of cell death, such as ferroptosis, holds great promise as a viable and effective intervention. METHODS: We analyzed online database data and collected clinical samples to verify the expression and function of BMAL1 in AML. We conducted experiments on AML cell proliferation, cell cycle, ferroptosis, and chemotherapy resistance by overexpressing/knocking down BMAL1 and using assays such as MDA detection and BODIPY 581/591 C11 staining. We validated the transcriptional regulation of HMGB1 by BMAL1 through ChIP assay, luciferase assay, RNA level detection, and western blotting. Finally, we confirmed the results of our cell experiments at the animal level. RESULTS: BMAL1 up-regulation is an observed phenomenon in AML patients. Furthermore, there existed a strong correlation between elevated levels of BMAL1 expression and inferior prognosis in individuals with AML. We found that knocking down BMAL1 inhibited AML cell growth by blocking the cell cycle. Conversely, overexpressing BMAL1 promoted AML cell proliferation. Moreover, our research results revealed that BMAL1 inhibited ferroptosis in AML cells through BMAL1-HMGB1-GPX4 pathway. Finally, knocking down BMAL1 can enhance the efficacy of certain first-line cancer therapeutic drugs, including venetoclax, dasatinib, and sorafenib. CONCLUSION: Our research results suggest that BMAL1 plays a crucial regulatory role in AML cell proliferation, drug resistance, and ferroptosis. BMAL1 could be a potential important therapeutic target for AML.


Assuntos
Fatores de Transcrição ARNTL , Resistencia a Medicamentos Antineoplásicos , Ferroptose , Proteína HMGB1 , Leucemia Mieloide Aguda , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Transdução de Sinais , Animais , Feminino , Humanos , Masculino , Camundongos , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Proteína HMGB1/metabolismo , Proteína HMGB1/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/genética , Camundongos Nus , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Prognóstico , Sulfonamidas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Zool Res ; 45(3): 535-550, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38747058

RESUMO

Proper regulation of synapse formation and elimination is critical for establishing mature neuronal circuits and maintaining brain function. Synaptic abnormalities, such as defects in the density and morphology of postsynaptic dendritic spines, underlie the pathology of various neuropsychiatric disorders. Protocadherin 17 (PCDH17) is associated with major mood disorders, including bipolar disorder and depression. However, the molecular mechanisms by which PCDH17 regulates spine number, morphology, and behavior remain elusive. In this study, we found that PCDH17 functions at postsynaptic sites, restricting the number and size of dendritic spines in excitatory neurons. Selective overexpression of PCDH17 in the ventral hippocampal CA1 results in spine loss and anxiety- and depression-like behaviors in mice. Mechanistically, PCDH17 interacts with actin-relevant proteins and regulates actin filament (F-actin) organization. Specifically, PCDH17 binds to ROCK2, increasing its expression and subsequently enhancing the activity of downstream targets such as LIMK1 and the phosphorylation of cofilin serine-3 (Ser3). Inhibition of ROCK2 activity with belumosudil (KD025) ameliorates the defective F-actin organization and spine structure induced by PCDH17 overexpression, suggesting that ROCK2 mediates the effects of PCDH17 on F-actin content and spine development. Hence, these findings reveal a novel mechanism by which PCDH17 regulates synapse development and behavior, providing pathological insights into the neurobiological basis of mood disorders.


Assuntos
Citoesqueleto de Actina , Caderinas , Espinhas Dendríticas , Protocaderinas , Quinases Associadas a rho , Animais , Camundongos , Citoesqueleto de Actina/metabolismo , Caderinas/metabolismo , Caderinas/genética , Espinhas Dendríticas/metabolismo , Espinhas Dendríticas/fisiologia , Regulação da Expressão Gênica , Quinases Associadas a rho/metabolismo , Quinases Associadas a rho/genética , Protocaderinas/genética , Protocaderinas/metabolismo
4.
Signal Transduct Target Ther ; 9(1): 51, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38424048

RESUMO

Mutations in the Contactin-associated protein-like 2 (CNTNAP2) gene are associated with autism spectrum disorder (ASD), and ectodomain shedding of the CNTNAP2 protein plays a role in its function. However, key enzymes involved in the C-terminal cleavage of CNTNAP2 remain largely unknown, and the effect of ASD-associated mutations on this process and its role in ASD pathogenesis remain elusive. In this report we showed that CNTNAP2 undergoes sequential cleavages by furin, ADAM10/17-dependent α-secretase and presenilin-dependent γ-secretase. We identified that the cleavage sites of ADAM10 and ADAM17 in CNTNAP2 locate at its C-terminal residue I79 and L96, and the main α-cleavage product C79 by ADAM10 is required for the subsequent γ-secretase cleavage to generate CNTNAP2 intracellular domain (CICD). ASD-associated CNTNAP2 mutations impair the α-cleavage to generate C79, and the inhibition leads to ASD-like repetitive and social behavior abnormalities in the Cntnap2-I1254T knock-in mice. Finally, exogenous expression of C79 improves autism-like phenotypes in the Cntnap2-I1254T knock-in and Cntnap2-/- knockout mice. This data demonstrates that the α-secretase is essential for CNTNAP2 processing and its function. Our study indicates that inhibition of the cleavage by pathogenic mutations underlies ASD pathogenesis, and upregulation of its C-terminal fragments could have therapeutical potentials for ASD treatment.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Animais , Camundongos , Secretases da Proteína Precursora do Amiloide/genética , Transtorno do Espectro Autista/genética , Mutação/genética , Camundongos Knockout , Contactinas/genética , Fenótipo , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética
5.
J Imaging Inform Med ; 37(1): 363-373, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38343208

RESUMO

We aimed to develop machine learning (ML)-based algorithms to assist physicians in ultrasound-guided localization of cricoid cartilage (CC) and thyroid cartilage (TC) in cricothyroidotomy. Adult female volunteers were prospectively recruited from two hospitals between September and December, 2020. Ultrasonographic images were collected via a modified longitudinal technique. You Only Look Once (YOLOv5s), Faster Regions with Convolutional Neural Network features (Faster R-CNN), and Single Shot Detector (SSD) were selected as the model architectures. A total of 488 women (mean age: 36.0 years) participated in the study, contributing to a total of 292,053 frames of ultrasonographic images. The derived ML-based algorithms demonstrated excellent discriminative performance for the presence of CC (area under the receiver operating characteristic curve [AUC]: YOLOv5s, 0.989, 95% confidence interval [CI]: 0.982-0.994; Faster R-CNN, 0.986, 95% CI: 0.980-0.991; SSD, 0.968, 95% CI: 0.956-0.977) and TC (AUC: YOLOv5s, 0.989, 95% CI: 0.977-0.997; Faster R-CNN, 0.981, 95% CI: 0.965-0.991; SSD, 0.982, 95% CI: 0.973-0.990). Furthermore, in the frames where the model could correctly indicate the presence of CC or TC, it also accurately localized CC (intersection-over-union: YOLOv5s, 0.753, 95% CI: 0.739-0.765; Faster R-CNN, 0.720, 95% CI: 0.709-0.732; SSD, 0.739, 95% CI: 0.726-0.751) or TC (intersection-over-union: YOLOv5s, 0.739, 95% CI: 0.722-0.755; Faster R-CNN, 0.709, 95% CI: 0.687-0.730; SSD, 0.713, 95% CI: 0.695-0.730). The ML-based algorithms could identify anatomical landmarks for cricothyroidotomy in adult females with favorable discriminative and localization performance. Further studies are warranted to transfer this algorithm to hand-held portable ultrasound devices for clinical use.

6.
FEBS J ; 291(3): 445-457, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37909373

RESUMO

The circadian clock is generated by a molecular timekeeping mechanism coordinating daily oscillations of physiology and behaviors in mammals. In the mammalian circadian clockwork, basic helix-loop-helix ARNT-like protein 1 (BMAL1) is a core circadian component whose defects lead to circadian disruption and elicit behavioral arrhythmicity. To identify previously unknown regulators for circadian clocks, we searched for genes influencing BMAL1 protein level by using a CRISPR/Cas9-based genome-wide knockout library. As a result, we found that the deubiquitinase ubiquitin carboxyl-terminal hydrolase 1 (USP1) positively affects BMAL1 protein abundance. Overexpression of wild-type USP1, but not a deubiquitinase-inactive mutant USP1, upregulated BMAL1 protein level, whereas genetic ablation of USP1 downregulated BMAL1 protein level in U2OS cells. Furthermore, treatment with USP1 inhibitors led to significant downregulation of BMAL1 protein in U2OS cells as well as mouse tissues. Subsequently, genetic ablation or pharmacological inhibition of USP1 resulted in reduced mRNA levels of a panel of clock genes and disrupted circadian rhythms in U2OS cells. Mechanistically, USP1 was able to de-ubiquitinate BMAL1 and inhibit the proteasomal degradation of BMAL1. Interestingly, the expression of Usp1 was much higher than the other two deubiquitinases of BMAL1 (Usp2 and Usp9X) in the mouse heart, implying a tissue-specific function of USP1 in the regulation of BMAL1 stability. Our work thus identifies deubiquitinase USP1 as a previously unknown regulator of the mammalian circadian clock and highlights the potential of genome-wide CRISPR screens in the identification of regulators for the circadian clock.


Assuntos
Relógios Circadianos , Animais , Camundongos , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Relógios Circadianos/genética , Ritmo Circadiano/genética , Enzimas Desubiquitinantes , Humanos
7.
JCI Insight ; 8(16)2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37606043

RESUMO

Attention-deficit hyperactivity disorder (ADHD) is a highly heritable neurodevelopmental disorder that affects approximately 5.3% of children and approximately 2.5% of adults. There is an intimate relationship between ADHD and sleep disturbance. Specifically, individuals carry a mutation in the core circadian gene CRY1 (c. 1657 + 3A > C), which results in the deletion of exon 11 expression in the CRY1 protein (CRY1Δ11), causing them to exhibit typical ADHD symptoms. However, the underlying mechanism is still elusive. In this study, we demonstrate that Cry1Δ11 (c. 1717 + 3A > C) mice showed ADHD-like symptoms, including hyperactivity, impulsivity, and deficits in learning and memory. A hyperactive cAMP signaling pathway was found in the nucleus accumbens (NAc) of Cry1Δ11 mice. We further demonstrated that upregulated c-Fos was mainly localized in dopamine D1 receptor-expressing medium spiny neurons (DRD1-MSNs) in the NAc. Neuronal excitability of DRD1-MSNs in the NAc of Cry1Δ11 mice was significantly higher than that of WT controls. Mechanistically, the CRY1Δ11 protein, in contrast to the WT CRY1 protein, failed to interact with the Gαs protein and inhibit DRD1 signaling. Finally, the DRD1 antagonist SCH23390 normalized most ADHD-like symptoms in Cry1Δ11 mice. Thus, our results reveal hyperactive DRD1 signaling as an underlying mechanism and therapeutic target for ADHD induced by the highly prevalent CRY1Δ11 mutation.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Animais , Camundongos , Transtorno do Deficit de Atenção com Hiperatividade/genética , Receptores de Dopamina D1/genética , Transdução de Sinais , Éxons , Mutação
8.
Signal Transduct Target Ther ; 8(1): 219, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37271769

RESUMO

As the most prevalent neurodevelopmental disorders in children, autism spectrum disorders (ASD) are characterized by deficits in language development, social interaction, and repetitive behaviors or inflexible interests. Contactin associated protein like 2 (CNTNAP2), encoding a single transmembrane protein (CNTNAP2) with 1331 amino acid residues, is a widely validated ASD-susceptible gene. Cntnap2-deficient mice also show core autism-relevant behaviors, including the social deficits and repetitive behavior. However, the cellular mechanisms underlying dysfunction CNTNAP2 and ASD remain elusive. In this study, we found a motif within the transmembrane domain of CNTNAP2 was highly homologous to the γ-secretase cleavage site of amyloid-ß precursor protein (APP), suggesting that CNTNAP2 may undergo proteolytic cleavage. Further biochemical analysis indicated that CNTNAP2 is cleaved by γ-secretase to produce the CNTNAP2 intracellular domain (CICD). Virally delivery of CICD to the medial prefrontal cortex (mPFC) in Cntnap2-deficient (Cntnap2-/-) mice normalized the deficit in the ASD-related behaviors, including social deficit and repetitive behaviors. Furthermore, CICD promoted the nuclear translocation of calcium/calmodulin-dependent serine protein kinase (CASK) to regulate the transcription of genes, such as Prader Willi syndrome gene Necdin. Whereas Necdin deficiency led to reduced social interaction in mice, virally expression of Necdin in the mPFC normalized the deficit in social preference of Cntnap2-/- mice. Our results thus reveal a critical function of CICD and highlight a role of the CNTNAP2-CASK-Necdin signaling pathway in ASD.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Camundongos , Animais , Transtorno Autístico/genética , Secretases da Proteína Precursora do Amiloide , Transtorno do Espectro Autista/genética , Transdução de Sinais , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética
9.
Mol Brain ; 16(1): 33, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-37020302

RESUMO

FMRP, an RNA-binding protein, has previously shown to be involved in regulation of circadian rhythms in flies and mice. However, the molecular mechanism remains elusive. Here we demonstrate that core circadian component Per1 mRNA was a target of FMRP and the association leads to reduced PER1 expression. In Fmr1 KO mice, the oscillation of PER1 protein expression was significantly affected in a temporal and tissue-dependent pattern when compared to WT mice. Our work thus identified Per1 mRNA as a novel target of FMRP and suggested a potential role of FMRP in regulation of circadian function.


Assuntos
Ritmo Circadiano , Fatores de Transcrição , Camundongos , Animais , RNA Mensageiro , Fatores de Transcrição/metabolismo , Ritmo Circadiano/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Proteínas Circadianas Period/metabolismo
10.
Front Bioeng Biotechnol ; 11: 1052607, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36845170

RESUMO

Exogenous insulin therapy is the mainstay treatment for Type-1 diabetes (T1D) caused by insulin deficiency. A fine-tuned insulin supply system is important to maintain the glucose homeostasis. In this study, we present a designed cell system that produces insulin under an AND gate control, which is triggered only in the presence of both high glucose and blue light illumination. The glucose-sensitive GIP promoter induces the expression of GI-Gal4 protein, which forms a complex with LOV-VP16 in the presence of blue light. The GI-Gal4:LOV-VP16 complex then promotes the expression of UAS-promoter-driven insulin. We transfected these components into HEK293T cells, and demonstrated the insulin was secreted under the AND gate control. Furthermore, we showed the capacity of the engineered cells to improve the blood glucose homeostasis through implantation subcutaneously into Type-1 diabetes mice.

11.
Hum Mol Genet ; 32(10): 1722-1729, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-36694982

RESUMO

Isolated hypogonadotropic hypogonadism (IHH) is a rare disease with hypogonadism and infertility caused by the defects in embryonic migration of hypothalamic gonadotropin-releasing hormone (GnRH) neurons, hypothalamic GnRH secretion or GnRH signal transduction. PROKR2 gene, encoding a G-protein coupled receptor PROKR2, is one of the most frequently mutated genes identified in IHH patients. However, the functional consequences of several PROKR2 mutants remain elusive. In this study, we systematically analyzed the Gαq, Gαs and ERK1/2 signaling of 23 IHH-associated PROKR2 mutations which are yet to be functionally characterized. We demonstrate that blockage of Gαq, instead of MAPK/ERK pathway, inhibited PROK2-induced migration of PROKR2-expressing cells, implying that PROKR2-related IHH results primarily due to Gαq signaling pathway disruption. Combined with previous reports, we categorized a total of 63 IHH-associated PROKR2 mutations into four distinct groups according Gαq pathway functionality: (i) neutral (N, >80% activity); (ii) low pathogenicity (L, 50-80% activity); (iii) medium pathogenicity (M, 20-50% activity) and (iv) high pathogenicity (H, <20% activity). We further compared the cell-based functional results with in silico mutational prediction programs. Our results indicated that while Sorting Intolerant from Tolerant predictions were accurate for transmembrane region mutations, mutations localized in the intracellular and extracellular domains were accurately predicted by the Combined Annotation Dependent Depletion prediction tool. Our results thus provide a functional database that can be used to guide diagnosis and appropriate genetic counseling in IHH patients with PROKR2 mutations.


Assuntos
Hipogonadismo , Humanos , Hipogonadismo/genética , Mutação , Hormônio Liberador de Gonadotropina/genética , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais , Gonadotropinas , Receptores de Peptídeos/genética
12.
Cell Rep ; 42(1): 112012, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36680774

RESUMO

Long bones are generated by mesoderm-derived skeletal progenitor/stem cells (SSCs) through endochondral ossification, a process of sequential chondrogenic and osteogenic differentiation tightly controlled by the synergy between intrinsic and microenvironment cues. Here, we report that loss of TRIM28, a transcriptional corepressor, in mesoderm-derived cells expands the SSC pool, weakens SSC osteochondrogenic potential, and endows SSCs with properties of ectoderm-derived neural crest cells (NCCs), leading to severe defects of skeletogenesis. TRIM28 preferentially enhances H3K9 trimethylation and DNA methylation on chromatin regions more accessible in NCCs; loss of this silencing upregulates neural gene expression and enhances neurogenic potential. Moreover, TRIM28 loss causes hyperexpression of GREM1, which is an extracellular signaling factor promoting SSC self-renewal and SSC neurogenic potential by activating AKT/mTORC1 signaling. Our results suggest that TRIM28-mediated chromatin silencing establishes a barrier for maintaining the SSC lineage trajectory and preventing a transition to ectodermal fate by regulating both intrinsic and microenvironment cues.


Assuntos
Osteogênese , Proteína 28 com Motivo Tripartido , Diferenciação Celular/genética , Cromatina , Expressão Gênica , Proteínas Proto-Oncogênicas c-akt/genética , Células-Tronco , Serina-Treonina Quinases TOR/genética , Animais , Camundongos , Proteína 28 com Motivo Tripartido/metabolismo , Transdução de Sinais
13.
Sci Adv ; 8(47): eadd6391, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36417528

RESUMO

GGC repeat expansions within NOTCH2NLC have been identified as the genetic cause of neuronal intranuclear inclusion disease (NIID). To understand the molecular pathogenesis of NIID, here, we established both a transgenic mouse model and a human neural progenitor cells (hNPCs) model. Expression of the NOTCH2NLC with expanded GGC repeats produced widespread intranuclear and perinuclear polyglycine (polyG), polyalanine (polyA), and polyarginine (polyR) inclusions, leading to behavioral deficits and severe neurodegeneration, which faithfully mimicked the clinical and pathological features associated with NIID. Furthermore, conserved alternative splicing events were identified between the NIID mouse and hNPC models, among which was the enrichment of the binding motifs of hnRNPM, an RNA binding protein known as alternative splicing regulator. Expanded NOTCH2NLC-polyG and NOTCH2NLC-polyA could interact with and sequester hnRNPM, while overexpression of hnRNPM could ameliorate the cellular toxicity. These results together suggested that dysfunction of hnRNPM could play an important role in the molecular pathogenesis of NIID.


Assuntos
Corpos de Inclusão Intranuclear , Doenças Neurodegenerativas , Animais , Humanos , Camundongos , Modelos Animais de Doenças , Corpos de Inclusão Intranuclear/genética , Corpos de Inclusão Intranuclear/patologia , Doenças Neurodegenerativas/genética , Proteínas de Ligação a RNA
14.
Horm Res Paediatr ; 95(4): 384-392, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35797970

RESUMO

INTRODUCTION: Idiopathic hypogonadotropic hypogonadism (IHH) is a rare reproductive disorder resulting from gonadotropin-releasing hormone (GnRH) deficiency. However, in only approximately half of patients with IHH is it possible to identify a likely molecular diagnosis. Mice lacking Slit2 have a reduced number or altered patterning of GnRH neurons in the brain. In order to assess the contribution of SLIT2 to IHH, we carried out a candidate gene burden test analysis. METHODS: A total of 196 IHH probands and 2,362 ethic-matched controls were recruited for this study. The IHH probands and controls were subjected to whole-exome sequencing. In the IHH patients with SLIT2 variants and their available family members, detailed phenotyping and segregation analysis were performed. RESULTS: Nine heterozygous SLIT2 rare sequencing variants (RSVs) were identified in 13 probands, with a prevalence of 6.6%. Furthermore, we identified an increased mutational burden for SLIT2 in this cohort (odds ratio = 2.2, p = 0.021). The segregation analysis of available IHH families revealed that the majority of SLIT2 RSVs were inherited from unaffected or partially affected parents. CONCLUSION: Our study suggests SLIT2 as a new IHH-associated gene and expands the clinical and genetic spectrum of IHH. Furthermore, SLIT2 alone does not appear to be sufficient to cause the disorder, and it may interact with other IHH-associated genes to induce a clinical phenotype.


Assuntos
Hipogonadismo , Animais , Hormônio Liberador de Gonadotropina/genética , Heterozigoto , Humanos , Hipogonadismo/epidemiologia , Hipogonadismo/genética , Camundongos , Mutação , Fenótipo
15.
Front Bioeng Biotechnol ; 10: 854880, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35685094

RESUMO

Knowledge of mandibular growth and development is essential for diagnosis of malformation and early interception. A previous method of quantifying mandibular growth using the distances between selected anatomical landmarks over the growth period does not provide a complete, quantitative description of the continuous growth patterns. The current study aimed to bridge the gap by measuring the 3D continuous growth of the mandible in miniature pigs using cone-beam computerized tomography (CBCT). The mandibles of the pigs were CBCT-scanned monthly over 12 months, and the 3D mandibular models were reconstructed. A new non-linear, time-dependent osteometric modeling approach was developed to register two consecutive mandible models by searching for the corresponding points with the highest likelihood of matching the anatomical and morphological features so that the morphological changes patterns for each month could be described using color maps on the models. The morphological changes of the mandible were found to decrease anteriorly, with the condyle region and the posterior part of the ramus growing faster than the rest of the mandible. The condyle region showed the fastest growth rate and the posterior ramus the second during the growth period, while the middle and anterior corpus regions showed the slowest growth rates. In conclusion, the current results revealed the non-linear patterns and rates of morphological changes in different growth regions and the whole mandible. The new approach may also be useful for future studies on the growth of the mandible in other animals.

16.
Prog Neurobiol ; 216: 102310, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35724808

RESUMO

The etiology of epilepsy remains undefined in two-thirds of patients. Here, we identified a de novo variant of ATP1A2 (c.2426 T > G, p.Leu809Arg), which encodes the α2 subunit of Na+/K+-ATPase, from a family with idiopathic epilepsy. This variant caused epilepsy with hemiplegic migraine in the study patients. We generated the point variant mouse model Atp1a2L809R, which recapitulated the epilepsy observed in the study patients. In Atp1a2L809R/WT mice, convulsions were observed and cognitive and memory function was impaired. This variant affected the potassium binding function of the protein, disabling its ion transport ability, thereby increasing the frequency of nerve impulses. Valproate (VPA) and Carbamazepine (CBZ) have limited therapeutic efficacy in ameliorating the epileptic syndromes of Atp1a2L809R/WT mice. Our work revealed that ATP1A2L809R variants cause a predisposition to epilepsy. Moreover, we provide a point variant mouse model for epilepsy research and drug screening.


Assuntos
Epilepsia , Enxaqueca com Aura , Animais , Modelos Animais de Doenças , Epilepsia/genética , Camundongos , Enxaqueca com Aura/genética , Enxaqueca com Aura/metabolismo , Mutação , ATPase Trocadora de Sódio-Potássio/genética , ATPase Trocadora de Sódio-Potássio/metabolismo
17.
Int J Endocrinol ; 2021: 7752526, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721574

RESUMO

Semaphorin (SEMA) has an important role in nerve development, organ formation, immune response, angiogenesis, and tumor growth. SEMA can regulate the growth and branching of axons, the morphology of dendrites, and the migration of neurons. The loss-of-function in SEMA and its receptors PLXNs and NRP affect the migration of GnRH neurons, leading to idiopathic hypogonadotropic hypogonadism (IHH). As a member of the SEMA family, SEMA3A has an important role in axonal rejection, dendritic branching, synaptic formation, and neuronal migration. There are more and more SEMA3A variants identified in IHH patients. In this study, we identified a novel SEMA3A variant (c.1369A > G (p.T457A)) in a male nIHH patient. Functional studies indicated that the T457A SEMA3A variant led to the defect of FAK phosphorylation and GN11 cell migration, which strongly argued in favor of its pathogenic effect in the nIHH patient. Our findings substantiated that the 435-457 position of SEMA3A might be very important for the secretion of SEMA3A. Haploin-sufficiency of SEMA3A in humans was sufficient to cause the IHH phenotype. SEMA3A variants might have a role in modifying the IHH phenotype, according to the variants at different positions of SEMA3A. SEMAs and its receptors formed a complex network, and other members of the SEMA-signaling pathway might also be involved in the pathogenesis of IHH.

18.
Mol Genet Genomic Med ; 9(11): e1816, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34636164

RESUMO

BACKGROUND: Isolated hypogonadotropic hypogonadism (IHH) is a clinical syndrome described by failure of gonadal function secondary to defects on the synthesis, secretion, or action of the gonadotropin-releasing hormone (GnRH). The secreted glycoprotein SEMA3A binds its receptors NRP1 or NRP2 and PLXNA to participate in axonal projection, dendritic branching, synaptic formation, and neuronal migration. Deficiency in SEMA3A, NRP1, NRP2, and PLXNA1 have been related to abnormal GnRH neuron development in mice and IHH in humans. METHODS: The aim of this study was to examine the genotypic and phenotypic spectra of the NRP1, NRP2, and PLXNA1 genes in a large cohort of IHH probands from China. We screened NRP1, NRP2, and PLXNA1 variants in Chinese IHH patients by whole exome sequencing and pedigree analysis. RESULTS: We identified 10 heterozygous missense variants in PLXNA1, five heterozygous missense variants in NRP1, and two heterozygous missense variants in NRP2. NRP1 variants were found only in IHH patients with defective olfaction (i.e., Kallmann syndrome, KS). In addition, 85% (17/20) of patients harbored variants in other IHH-associated genes. CONCLUSION: Our study greatly enriched the genotypic and phenotypic spectra of PLXNA1, NRP1, and NRP2 in IHH. It may be conducive to the genetic counseling, diagnosis, and treatment of IHH with mutations in the PLXNA1, NRP1, and NRP2 genes. Furthermore, our results indicated that NRP1 were strongly linked to hearing loss.


Assuntos
Hipogonadismo , Animais , Genótipo , Humanos , Hipogonadismo/genética , Camundongos , Mutação , Proteínas do Tecido Nervoso/genética , Neuropilina-1 , Neuropilina-2 , Fenótipo , Receptores de Superfície Celular/genética , Sequenciamento do Exoma
19.
Int J Mol Sci ; 22(19)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34639006

RESUMO

Breast cancer development is associated with macrophage infiltration and differentiation in the tumor microenvironment. Our previous study highlights the crucial function of reactive oxygen species (ROS) in enhancing macrophage infiltration during the disruption of mammary tissue polarity. However, the regulation of ROS and ROS-associated macrophage infiltration in breast cancer has not been fully determined. Previous studies identified retinoid orphan nuclear receptor alpha (RORα) as a potential tumor suppressor in human breast cancer. In the present study, we showed that retinoid orphan nuclear receptor alpha (RORα) significantly decreased ROS levels and inhibited ROS-mediated cytokine expression in breast cancer cells. RORα expression in mammary epithelial cells inhibited macrophage infiltration by repressing ROS generation in the co-culture assay. Using gene co-expression and chromatin immunoprecipitation (ChIP) analyses, we identified complex I subunits NDUFS6 and NDUFA11 as RORα targets that mediated its function in suppressing superoxide generation in mitochondria. Notably, the expression of RORα in 4T1 cells significantly inhibited cancer metastasis, reduced macrophage accumulation, and enhanced M1-like macrophage differentiation in tumor tissue. In addition, reduced RORα expression in breast cancer tissue was associated with an increased incidence of cancer metastasis. These results provide additional insights into cancer-associated inflammation, and identify RORα as a potential target to suppress ROS-induced mammary tumor progression.


Assuntos
Complexo I de Transporte de Elétrons/metabolismo , Neoplasias/metabolismo , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Biomarcadores , Respiração Celular , Citocinas/metabolismo , Metabolismo Energético , Regulação Neoplásica da Expressão Gênica , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias/genética , Neoplasias/patologia , Microambiente Tumoral , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/metabolismo
20.
PeerJ ; 9: e11629, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34221726

RESUMO

BACKGROUND: The outbreak of COVID-19 has been defined by the World Health Organization as a pandemic, and containment depends on traditional public health measures. However, the explosive growth of the number of infected cases in a short period of time has caused tremendous pressure on medical systems. Adequate isolation facilities are essential to control outbreaks, so this study aims to quickly estimate the demand and number of isolation beds. METHODS: We established a discrete simulation model for epidemiology. By adjusting or fitting necessary epidemic parameters, the effects of the following indicators on the development of the epidemic and the occupation of medical resources were explained: (1) incubation period, (2) response speed and detection capacity of the hospital, (3) disease healing time, and (4) population mobility. Finally, a method for predicting the number of isolation beds was summarized through multiple linear regression. This is a city level model that simulates the epidemic situation from the perspective of population mobility. RESULTS: Through simulation, we show that the incubation period, response speed and detection capacity of the hospital, disease healing time, degree of population mobility, and infectivity of cured patients have different effects on the infectivity, scale, and duration of the epidemic. Among them, (1) incubation period, (2) response speed and detection capacity of the hospital, (3) disease healing time, and (4) population mobility have a significant impact on the demand and number of isolation beds (P <0.05), which agrees with the following regression equation: N = P × (-0.273 + 0.009I + 0.234M + 0.012T1 + 0.015T2) × (1 + V).

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