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1.
Adv Pharm Bull ; 14(2): 469-482, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39206403

ABSTRACT

Purpose: Neovascular age-related macular degeneration (nAMD) is a prevalent cause of blindness in the elderly. Standard treatment includes anti-vascular endothelial growth factor (anti-VEGF) drugs, such as aflibercept. However, anti-VEGF drugs may have limited efficacy and cause drug resistance. This study explores whether Kavain, an anti-inflammatory molecule from Piper methysticum, can treat choroidal neovascularization (CNV). Methods: Various experiments were conducted to assess the Kavain's toxicity. The impact of Kavain on in vitro cultured endothelial cells was examined through 5-ethynyl-20-deoxyuridine (EdU) assays, transwell migration assays, and tube formation assays. The therapeutic effects of Kavain on CNV were investigated using a laser-induced CNV mice model. To elucidate the mechanism of Kavain, network pharmacology analysis, molecular docking, and western blots were performed. Results: Kavain exhibited no apparent toxicity both in vitro and in vivo. Kavain significantly decreased endothelial cell viability, proliferation, migration, and tube formation ability in a dose-dependent manner compared to the hypoxia groups (P<0.05). Kavain alleviated CNV in the laser-induced CNV mouse model compared to the control groups (P<0.05). These effects were statistically significantly enhanced in the Kavain plus aflibercept groups (P<0.05). Following Kavain administration, the expression levels of various inflammatory factors were markedly reduced in retinal pigment epithelium (RPE)/choroid complexes (P<0.05). Mechanistically, Kavain decreased the activity of the hypoxia-inducible factor 1α (HIF-1α)/VEGF-A/ VEGF receptor 2 (VEGFR2) signaling pathway. Conclusion: Our study is the first to demonstrate Kavain's potential as a promising treatment for nAMD, owing to its dual effects of anti-inflammation and anti-angiogenesis.

2.
Adv Healthc Mater ; 13(22): e2400254, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38857027

ABSTRACT

Lipid-lowering drugs, especially statins, are extensively utilized in clinical settings for the prevention of hyperlipidemia. Nevertheless, prolonged usage of current lipid-lowering medications is associated with significant adverse reactions. Therefore, it is imperative to develop novel therapeutic agents for lipid-lowering therapy. In this study, a chenodeoxycholic acid and lactobionic acid double-modified polyethyleneimine (PDL) nanocomposite as a gene delivery vehicle for lipid-lowering therapy by targeting the liver, are synthesized. Results from the in vitro experiments demonstrate that PDL exhibits superior transfection efficiency compared to polyethyleneimine in alpha mouse liver 12 (AML12) cells and effectively carries plasmids. Moreover, PDL can be internalized by AML12 cells and rapidly escape lysosomal entrapment. Intravenous administration of cyanine5.5 (Cy5.5)-conjugated PDL nanocomposites reveals their preferential accumulation in the liver compared to polyethyleneimine counterparts. Systemic delivery of low-density lipoprotein receptor plasmid-loaded PDL nanocomposites into mice leads to reduced levels of low-density lipoprotein cholesterol (LDL-C) and triglycerides (TC) in the bloodstream without any observed adverse effects on mouse health or well-being. Collectively, these findings suggest that low-density lipoprotein receptor plasmid-loaded PDL nanocomposites hold promise as potential therapeutics for lipid-lowering therapy.


Subject(s)
Chenodeoxycholic Acid , Liver , Nanocomposites , Polyethyleneimine , Receptors, LDL , Animals , Polyethyleneimine/chemistry , Mice , Liver/metabolism , Liver/drug effects , Chenodeoxycholic Acid/chemistry , Chenodeoxycholic Acid/pharmacology , Receptors, LDL/metabolism , Receptors, LDL/genetics , Nanocomposites/chemistry , Cell Line , Male , Transfection/methods , Gene Transfer Techniques , Plasmids/genetics , Plasmids/chemistry
3.
Biochem Biophys Res Commun ; 720: 150065, 2024 08 06.
Article in English | MEDLINE | ID: mdl-38749188

ABSTRACT

Neovascular eye diseases, including proliferative diabetic retinopathy and retinopathy of prematurity, is a major cause of blindness. Laser ablation and intravitreal anti-VEGF injection have shown their limitations in treatment of retinal neovascularization. Identification of a new therapeutic strategies is in urgent need. Our study aims to assess the effects of Cryptotanshinone (CPT), a natural compound derived from Salvia miltiorrhiza Bunge, in retina neovascularization and explore its potential mechanism. Our study demonstrated that CPT did not cause retina tissue toxicity at the tested concentrations. Intravitreal injections of CPT reduced pathological angiogenesis and promoted physical angiogenesis in oxygen-induced retinopathy (OIR) model. CPT improve visual function in OIR mice and reduced cell apoptosis. Moreover, we also revealed that CPT diminishes the expression of inflammatory cytokines in the OIR retina. In vitro, the administration of CPT effectively inhibited endothelial cells proliferation, migration, sprouting, and tube formation induced by the stimulation of human retinal vascular endothelial cells (HRVECs) with VEGF165. Mechanistically, CPT blocking the phosphorylation of VEGFR2 and downstream targeting pathway. After all, the findings demonstrated that CPT exhibits potent anti-angiogenic and anti-inflammatory effects in OIR mice, and it has therapeutic potential for the treatment of neovascular retinal diseases.


Subject(s)
Intravitreal Injections , Mice, Inbred C57BL , Phenanthrenes , Retinal Neovascularization , Animals , Phenanthrenes/pharmacology , Phenanthrenes/administration & dosage , Retinal Neovascularization/drug therapy , Retinal Neovascularization/pathology , Retinal Neovascularization/metabolism , Humans , Mice , Angiogenesis Inhibitors/pharmacology , Angiogenesis Inhibitors/administration & dosage , Cell Proliferation/drug effects , Cell Movement/drug effects , Apoptosis/drug effects , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Retina/drug effects , Retina/metabolism , Retina/pathology
5.
Adv Sci (Weinh) ; 11(9): e2306379, 2024 03.
Article in English | MEDLINE | ID: mdl-38115764

ABSTRACT

The hypothalamus in the brain plays a pivotal role in controlling energy balance in vertebrates. Nutritional excess through high-fat diet (HFD) feeding can dysregulate hypothalamic signaling at multiple levels. Yet, it remains largely unknown in what magnitude HFD feeding may impact epigenetics in this brain region. Here, it is shown that HFD feeding can significantly alter hypothalamic epigenetic events, including posttranslational histone modifications, DNA methylation, and chromatin accessibility. The authors comprehensively analyze the chromatin immunoprecipitation-sequencing (ChIP-seq), methylated DNA immunoprecipitation-sequencing (MeDIP-seq), single nucleus assay for transposase-accessible chromatin using sequencing (snATAC-seq), and RNA-seq data of the hypothalamus of C57 BL/6 mice fed with a chow or HFD for 1 to 6 months. The chromatins are categorized into 6 states using the obtained ChIP-seq data for H3K4me3, H3K27ac, H3K9me3, H3K27me3, and H3K36me3. A 1-month HFD feeding dysregulates histone modifications and DNA methylation more pronouncedly than that of 3- or 6-month. Besides, HFD feeding differentially impacts chromatin accessibility in hypothalamic cells. Thus, the epigenetic landscape is dysregulated in the hypothalamus of dietary obesity mice.


Subject(s)
DNA Methylation , Obesity , Mice , Animals , Obesity/genetics , DNA Methylation/genetics , Chromatin , Hypothalamus , Epigenesis, Genetic/genetics
7.
Medicine (Baltimore) ; 102(24): e34043, 2023 Jun 16.
Article in English | MEDLINE | ID: mdl-37327269

ABSTRACT

BACKGROUND: Adeno-associated virus (AAV) plays a vital role in ocular gene therapy and has been widely studied since 1996. This study summarizes and explores the publication outputs and future research trends of AAV-based ocular gene therapy. METHODS: Publications and data about AAV-based ocular gene therapy were downloaded from the Web of Science Core Collection or ClinicalTrials.gov database. The publications and data were analyzed by Microsoft Excel, CiteSpace, VOS viewer, and a free online platform (http://bibliometric.com). RESULTS: Totally 832 publications from the Web of Science Core Collection relevant to AAV-based ocular gene therapy were published from 1996 to 2022. These publications were contributed by research institutes from 42 countries or regions. The US contributed the most publications among these countries or regions, notably the University of Florida. Hauswirth WW was the most productive author. "Efficacy" and "safety" are the main focus areas for future research according to the references and keywords analysis. Eighty clinical trials examined AAV-based ocular gene therapy were registered on ClinicalTrials.Gov. Institutes from the US and European did the dominant number or the large proportion of the trials. CONCLUSIONS: The research focus of the AAV-based ocular gene therapy has transitioned from the study in biological theory to clinical trialing. The AAV-based gene therapy is not limited to inherited retinal diseases but various ocular diseases.


Subject(s)
Dependovirus , Face , Humans , Dependovirus/genetics , Retina , Bibliometrics , Genetic Therapy
8.
iScience ; 26(5): 106670, 2023 May 19.
Article in English | MEDLINE | ID: mdl-37168577

ABSTRACT

Hypothalamic pro-opiomelanocortin (POMC) neuron development is considered to play an essential role in the development of obesity. However, the underlying mechanisms remain unclear. Casein kinase 1α (CK1α) was expressed in the embryonic mouse hypothalamus at high levels and colocalized with POMC neurons. CK1α deletion in POMC neurons caused weight gain, metabolic defects, and increased food intake. The number of POMC-expressing cells was considerably decreased in Csnk1a1fl/fl;POMCcre (PKO) mice from embryonic day 15.5 to postnatal day 60, while apoptosis of POMC neurons was not affected. Furthermore, unchanged POMC progenitor cells and a decreased POMC phenotype established CK1α function in hypothalamic POMC neuron development. CK1α deletion led to elevated Notch intracellular domain (NICD) protein expression, and NICD inhibition rescued the PKO mouse phenotype. In summary, CK1α is involved in hypothalamic POMC expression via NICD-POMC signaling, deepening our understanding of POMC neuron development and control of systemic metabolic functions.

9.
Bioinform Biol Insights ; 17: 11779322231167977, 2023.
Article in English | MEDLINE | ID: mdl-37124128

ABSTRACT

Individuals with type 2 diabetes (T2D) and obesity have a higher risk of developing Alzheimer disease (AD), and increasing evidence indicates a link between impaired immune signaling pathways and the development of AD. However, the shared cellular mechanisms and molecular signatures among these 3 diseases remain unknown. The purpose of this study was to uncover similar molecular markers and pathways involved in obesity, T2D, and AD using bioinformatics and a network biology approach. First, we investigated the 3 RNA sequencing (RNA-seq) gene expression data sets and determined 224 commonly shared differentially expressed genes (DEGs) from obesity, T2D, and AD diseases. Gene ontology and pathway enrichment analyses revealed that mutual DEGs were mainly enriched with immune and inflammatory signaling pathways. In addition, we constructed a protein-protein interactions network for finding hub genes, which have not previously been identified as playing a critical role in these 3 diseases. Furthermore, the transcriptional factors and protein kinases regulating commonly shared DEGs among obesity, T2D, and AD were also identified. Finally, we suggested potential drug candidates as possible therapeutic interventions for 3 diseases. The results of this bioinformatics analysis provided a new understanding of the potential links between obesity, T2D, and AD pathologies.

10.
Life Sci ; 315: 121387, 2023 Feb 15.
Article in English | MEDLINE | ID: mdl-36640904

ABSTRACT

AIMS: Exosomes are a subpopulation of extracellular vesicles (EV) derived from multivesicular body (MVB) that transmit various cellular molecular constituents, including long noncoding RNAs (lncRNAs), to promote intercellular communication. Our aim was to investigate the function and mechanism of exosomal LINC00355 in gastric cancer cells. MAIN METHODS: Exosomal levels of LINC00355 in GC patients and healthy controls were measured by RT-qPCR. The effects of exosomal LINC00355 on GC cell viability, proliferation, migration and invasion were evaluated by CCK8, colony formation, Transwell and wound healing assays. The expression levels of Ki67 in xenograft tumor tissues were confirmed by immunohistochemistry assay, and apoptosis was analyzed by TUNEL apoptosis assay. Western blotting was used to monitor protein expression. RNA immunoprecipitation and RNA pulldown were performed to detect the interaction between LINC00355 and HDAC3. Chromatin immunoprecipitation was used to assess the interaction of HDAC3 with the TP53INP1 promoter. KEY FINDINGS: Exosomal LINC00355 levels were higher in plasma from gastric cancer patients than in plasma from healthy volunteers. Exosomal LINC00355 promoted the proliferation, migration and invasion of gastric cancer cell lines. RNA sequence analysis demonstrated that LINC00355 knockdown downregulated histone deacetylase HDAC3 and upregulated TP53INP1. Mechanistic investigation indicated that exosomal LINC00355 interacted with HDAC3 to suppress TP53INP1 transcription, which promoted epithelial-mesenchymal transition (EMT). SIGNIFICANCE: Exosomal LINC00355 plays a pivotal role in regulating EMT to induce the malignant progression of GC. Exosomal LINC00355 could be a promising biomarker in the early diagnosis and prognosis of GC.


Subject(s)
Exosomes , MicroRNAs , RNA, Long Noncoding , Stomach Neoplasms , Humans , Carrier Proteins/metabolism , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Exosomes/metabolism , Gene Expression Regulation, Neoplastic , Heat-Shock Proteins/metabolism , Histone Deacetylases/genetics , Histone Deacetylases/metabolism , MicroRNAs/genetics , RNA/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Stomach Neoplasms/pathology
11.
Brain Res Bull ; 185: 99-106, 2022 07.
Article in English | MEDLINE | ID: mdl-35525336

ABSTRACT

Obesity is believed to arise through the imbalance of energy homeostasis controlled by the central nervous system, where the hypothalamus plays the fundamental role in energy metabolism. In this review, we will provide an overview regarding the functions of POMC neurons and AgRP neurons in acute nucleus of the hypothalamus which mediated the energy metabolism, highlighting their interactions with peripheral organs derived hormones in control of energy homeostasis. Furthermore, the role of high fat diet induced hypothalamic microinflammation in the pathogenesis of obesity will be discussed. We hope this review could help researchers to understand the mechanism of hypothalamus in control of energy metabolism, and design related drugs to block the pathways involving in the impaired metabolism in obese patients.


Subject(s)
Diet, High-Fat , Hypothalamus , Diet, High-Fat/adverse effects , Energy Metabolism/physiology , Homeostasis/physiology , Humans , Hypothalamus/metabolism , Obesity/metabolism , Pro-Opiomelanocortin/metabolism
12.
ACS Nano ; 16(3): 4175-4185, 2022 03 22.
Article in English | MEDLINE | ID: mdl-35167250

ABSTRACT

Sperm motility can be enhanced by adding ATP exogenously during in vitro fertilization. However, administering exogenous ATP to the testis to improve sperm motility for in vivo asthenozoospermia treatment has not been investigated yet. Inspired by the recent advances in nanomedicine, we investigated whether the capability of drug delivery nanocarriers to traverse the blood-testis barrier (BTB) can facilitate ATP-dependent asthenozoospermia treatment. We found that the human H-ferritin (HFn) nanocarrier possesses the capability to traverse the BTB and specifically targets the head of elongated sperm cells. Specifically, the HFn nanocarrier traversed the BTB and accumulated in the sperm heads by binding with the HFn receptor (HFR), whose expression was relatively low in Sertoli cells but high in sperm heads. In a gossypol-induced mouse asthenozoospermia model, the administration of an ATP-loaded HFn nanocage through a tail vein injection significantly improved sperm motility. Moreover, the HFn nanocarrier was not toxic to mice in the short (1d) and long terms (30d, 90d) nor did it affect their reproductive health. Thus, the ATP-loaded HFn nanocarrier can potentially serve as a drug-delivery system for treating asthenozoospermia.


Subject(s)
Asthenozoospermia , Adenosine Triphosphate/metabolism , Animals , Apoferritins/metabolism , Asthenozoospermia/drug therapy , Asthenozoospermia/metabolism , Blood-Testis Barrier/metabolism , Ferritins/metabolism , Humans , Male , Mice , Sperm Motility , Spermatozoa/metabolism
13.
Ecotoxicol Environ Saf ; 231: 113184, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35032726

ABSTRACT

Ferrous iron and polysulfide (Fe(II)Sn aq) is a nano-decoction. It is usually prepared from the suspension of iron sulfide nanomaterial, using autoclave and centrifugation. A previous study conducted in our laboratory revealed that Fe(II)Sn aq was highly antibacterial, and it could efficiently kill more than 90% population of Escherichia coli and Staphylococcus aureus, within 5 min of the treatment. Our study reported that the intravenous administration of Fe(II)Sn aq provided effective treatment against epididymis infection, caused by S. aureus. The results of the study further highlighted its potential for clinical application. However, its effects on the reproductive system and overall health of mammals have not been investigated earlier. The present study assessed the impacts of Fe(II)Sn aq on reproductive health and other aspects of male mice. Briefly, male mice were exposed to Fe(II)Sn aq, either intravenously at the dose of 0.7 mM, 1.4 mM, and 2.8 mM of Fe2+or orally at the dose of 1.4 mM, 2.8 mM, and 5.6 mM of Fe2+. Following this, body weight, organs index, quality of sperm, blood biochemical markers, histopathology of organs, oxidative stress and apoptosis were evaluated, after 1 day and 30 days of exposure. In addition, male reproductivity was evaluated in terms of mating with female mice, and the body weight of the resulting offspring was recorded. Our results showed that the mice processed with Fe(II)Sn aq exhibited normal physiological status and reproductive capability. The present study illustrated the short- and long-term influences of Fe(II)Sn aq on the fertility of male mice for the first time. The findings of the study provided a valuable reference for the application of Fe(II)Sn aq, particularly in terms of reproductive safety.


Subject(s)
Epididymitis , Iron , Animals , Anti-Bacterial Agents/toxicity , Female , Male , Mice , Reproductive Health , Staphylococcus aureus , Sulfides
14.
J Biomed Res ; 37(3): 179-193, 2022 Nov 28.
Article in English | MEDLINE | ID: mdl-37013864

ABSTRACT

Erythropoietin-producing hepatocellular carcinoma A3 (EphA3) is a member of the largest subfamily of tyrosine kinase receptors-Eph receptors. Previous studies have shown that EphA3 is associated with tissue development. Recently, we have found that the expression of EphA3 is elevated in the hypothalamus of mice with diet-induced obesity (DIO). However, the role of EphA3 in hypothalamic-controlled energy metabolism remains unclear. In the current study, we demonstrated that the deletion of EphA3 in the hypothalamus by CRISPR/Cas9-mediated gene editing promotes obesity in male mice with high-fat diet feeding rather than those with normal chow diet feeding. Moreover, the deletion of hypothalamic EphA3 promotes high-fat DIO by increasing food intake and reducing energy expenditure. Knockdown of EphA3 leads to smaller intracellular vesicles in GT1-7 cells. The current study reveals that hypothalamic EphA3 plays important roles in promoting DIO.

15.
Cell Rep ; 37(3): 109868, 2021 10 19.
Article in English | MEDLINE | ID: mdl-34686338

ABSTRACT

Store-operated calcium entry (SOCE) is pivotal in maintaining intracellular Ca2+ level and cell function; however, its role in obesity development remains largely unknown. Here, we show that the stromal interaction molecule 1 (Stim1), an endoplasmic reticulum (ER) Ca2+ sensor for SOCE, is critically involved in obesity development. Pharmacological blockade of SOCE in the brain, or disruption of Stim1 in hypothalamic agouti-related peptide (AgRP)-producing neurons (ASKO), significantly ameliorates dietary obesity and its associated metabolic disorders. Conversely, constitutive activation of Stim1 in AgRP neurons leads to an obesity-like phenotype. We show that the blockade of SOCE suppresses general translation in neuronal cells via the 2',5'-oligoadenylate synthetase 3 (Oas3)-RNase L signaling. While Oas3 overexpression in AgRP neurons protects mice against dietary obesity, deactivation of RNase L in these neurons significantly abolishes the effect of ASKO. These findings highlight an important role of Stim1 and SOCE in the development of obesity.


Subject(s)
Agouti-Related Protein/metabolism , Calcium Signaling , Calcium/metabolism , Endoplasmic Reticulum/metabolism , Hypothalamus/metabolism , Neurons/metabolism , Obesity/prevention & control , Stromal Interaction Molecule 1/deficiency , 2',5'-Oligoadenylate Synthetase/metabolism , Agouti-Related Protein/genetics , Animals , Cell Line, Tumor , Diet, High-Fat , Disease Models, Animal , Endoribonucleases/metabolism , HEK293 Cells , Humans , Hypothalamus/physiopathology , Male , Mice, Inbred C57BL , Mice, Knockout , Obesity/genetics , Obesity/metabolism , Obesity/physiopathology , Stromal Interaction Molecule 1/genetics , Weight Gain
16.
In Vitro Cell Dev Biol Anim ; 57(4): 438-447, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33772408

ABSTRACT

Gonadotropin-releasing hormone (GnRH) is the initial central regulator of the animal reproduction system, which is crucial for puberty onset and fertility. However, the mechanisms regulating GnRH production and release remain unclear. In addition, few studies reported that miR-375 expressed in mouse hypothalamus, but up to now there are limited functional studies of miR-375 in regulating GnRH secretion. According to our recent findings that miR-375 was involved in regulating the synthesis and secretion of pituitary hormones, thus, we aimed to identify the role of miR-375 in regulating GnRH production in GT1-7 cells. Immunofluorescence results demonstrated that miR-375 was expressed in all of the GT1-7 cells. The functional studies showed that miR-375 overexpression enhanced GnRH mRNA expression level, but decreased the mRNA expressions of Sp1, Cebpb, Msx1, and Tle4. Transcriptomics analysis demonstrated Sp1 and Tle4 acted as the targeting genes of miR-375, and Sp1 negatively regulated Gnrh mRNA expression by binding to the Gnrh promoter. Thus, we conclude that miR-375 potentially enhances GnRH expression by targeting Sp1 and Tle4 in GT1-7 cells. Our results highlight a critical role of miR-375 in regulating GnRH production, which may provide a novel potential therapeutic approach to neuroendocrine-disorder-related dysfunctions.


Subject(s)
Gonadotropin-Releasing Hormone/genetics , MicroRNAs/genetics , Protein Kinases/genetics , Reproduction/genetics , Animals , Cell Line , Gene Expression Regulation/genetics , Hypothalamus/metabolism , Mice , Neurons/metabolism , Promoter Regions, Genetic , RNA, Messenger/genetics
17.
Cell Death Discov ; 6(1): 99, 2020.
Article in English | MEDLINE | ID: mdl-33083020

ABSTRACT

Long noncoding RNAs (LncRNAs) have been reported to play critical roles in gastric cancer, but true biomarkers remain unknown. In this study, we found a new lncRNA LINC00355 that was involved in malignant progression of gastric cancer (GC) and further revealed its role and mechanism. Differentially expressed lncRNAs were identified through bioinformatics, and qRT-PCR was used to validate the expression of LINC00355 in gastric cancer tissues and cells. The biological role of LINC00355 in GC was detected by gene overexpression and knockdown experiments. Subcellular fractionation, qRT-PCR, and FISH were performed to detect the subcellular localization. Co-IP and western blotting were used to study the ubiquitination-mediated regulation of P53 and the expression of the E3 ligases RAD18 and UBE3C. The results showed that LINC00355 was significantly increased in gastric cancer cell lines and patient tissues and closely correlated with late stages, distant metastasis, and poor prognosis of patients. High expression of LINC00355 promoted the proliferation and invasion of gastric cancer cells in vivo and in vitro. Mechanistic studies found that LINC00355 that mainly located in the nucleus, acting as a transcriptional activator, promoted transcription of RAD18 and UBE3C, which both bind to P53 and mediate the ubiquitination and degradation of P53. Furthermore, LINC00355 overexpression enhanced the ubiquitination process, and LINC00355 knockdown alleviated it. These results indicated that LINC00355 induces gastric cancer cell proliferation and invasion by promoting transcription of RAD18 and UBE3C, which mediates ubiquitination of P53 and thereby plays a critical role in survival and tumorigenicity of gastric cancer cells. LINC00355 may represent a new mechanism for GC progression and provide a potential marker for GC diagnosis and treatment.

18.
Proc Natl Acad Sci U S A ; 117(33): 20149-20158, 2020 08 18.
Article in English | MEDLINE | ID: mdl-32747560

ABSTRACT

The C2 domain containing protein extended synaptotagmin (E-Syt) plays important roles in both lipid homeostasis and the intracellular signaling; however, its role in physiology remains largely unknown. Here, we show that hypothalamic E-Syt3 plays a critical role in diet-induced obesity (DIO). E-Syt3 is characteristically expressed in the hypothalamic nuclei. Whole-body or proopiomelanocortin (POMC) neuron-specific ablation of E-Syt3 ameliorated DIO and related comorbidities, including glucose intolerance and dyslipidemia. Conversely, overexpression of E-Syt3 in the arcuate nucleus moderately promoted food intake and impaired energy expenditure, leading to increased weight gain. Mechanistically, E-Syt3 ablation led to increased processing of POMC to α-melanocyte-stimulating hormone (α-MSH), increased activities of protein kinase C and activator protein-1, and enhanced expression of prohormone convertases. These findings reveal a previously unappreciated role for hypothalamic E-Syt3 in DIO and related metabolic disorders.


Subject(s)
Gene Expression Regulation/physiology , Obesity/chemically induced , Obesity/genetics , Synaptotagmins/metabolism , Animals , Diet, High-Fat/adverse effects , Genetic Predisposition to Disease , Hypothalamus/metabolism , Male , Mice , Mice, Knockout , Neurons/metabolism , Proprotein Convertase 1/genetics , Proprotein Convertase 1/metabolism , Proprotein Convertase 2/genetics , Proprotein Convertase 2/metabolism , Synaptotagmins/genetics
19.
Nat Neurosci ; 23(7): 832-841, 2020 07.
Article in English | MEDLINE | ID: mdl-32451485

ABSTRACT

Prolonged obesity is associated with cerebrovascular dysfunction; however, the underlying mechanisms remain largely unclear. In the present study, using a prolonged obesity mouse model that suffers from basilar artery (BA) abnormalities, we find that microglial transforming growth factor ß-activated kinase 1 (Tak1) is over-activated in the brainstem. Both pharmacological inhibition primarily in the brainstem and genetic microglia-selective deletion of Tak1 ameliorated BA vascular dysfunction. Conversely, microglia-specific activation of Tak1 in the brainstem was sufficient to cause an impairment in BA function in chow-fed mice. Mechanistically, Tak1 activation leads to increased interleukin-18 (IL-18) production, whereas blockade of IL-18 receptor in the brain helped protect against cerebrovascular dysfunction despite prolonged obesity. Microglia-selective deletion of Tak1 also protects against ischemic stroke in prolonged obesity. Taken together, these findings provide evidence that microglial Tak1 in the brain, and particularly the brainstem, contributes to the pathogenesis of obesity-associated cerebrovascular dysfunction.


Subject(s)
Brain Stem/metabolism , MAP Kinase Kinase Kinases/metabolism , Microglia/metabolism , Obesity/metabolism , Animals , Basilar Artery/pathology , Brain/blood supply , Cerebrovascular Circulation/physiology , Diet, High-Fat/adverse effects , Male , Mice , Mice, Inbred C57BL , Stroke/metabolism
20.
J Invest Dermatol ; 139(1): 224-234, 2019 01.
Article in English | MEDLINE | ID: mdl-30081003

ABSTRACT

TWEAK acts by engaging with Fn14 to regulate inflammatory responses, fibrosis, and tissue remodeling, which are central in the repair processes of wounds. This study aims to explore the potential role of the TWEAK/Fn14 pathway in the healing of cutaneous burn wounds. Third-degree burns were introduced in wild-type and Fn14-deficient BALB/c mice, followed by evaluation of wound areas and histological changes. The downstream cytokines including growth factors were also examined in lesional skin. Moreover, human dermal microvascular endothelial cells and dermal fibroblasts were analyzed in vitro upon TWEAK stimulation. The healing of burn wounds was delayed in Fn14-deficient mice and was accompanied by the suppression of inflammatory responses, growth factor production, and extracellular matrix synthesis. Moreover, TWEAK/Fn14 activation enhanced the migration and cytokine production of both dermal microvascular endothelial cells and dermal fibroblasts. TWEAK also facilitates the expression of α-SMA and palladin in dermal fibroblasts. Furthermore, transfection of Fn14 small interfering RNA abrogated such promotion effect of TWEAK on these cells. In conclusion, TWEAK/Fn14 signals mediate the healing of burn wounds, possibly involving TWEAK regulation of the function of resident cells.


Subject(s)
Burns/genetics , Gene Expression Regulation , RNA/genetics , Skin/pathology , TWEAK Receptor/genetics , Wound Healing/genetics , Animals , Burns/metabolism , Burns/pathology , Cells, Cultured , Disease Models, Animal , Mice, Inbred BALB C , Mice, Knockout , Polymerase Chain Reaction , Signal Transduction , Skin/metabolism , TWEAK Receptor/biosynthesis
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