RESUMEN
Cholesterol homeostasis is essential for healthy mammalian cells and dysregulation of cholesterol metabolism contributes to the pathogenesis of various diseases including cancer. Cancer cells are dependent on cholesterol. Malignant progression is associated with high cellular demand for cholesterol, and extracellular cholesterol uptake is often elevated in cancer cell to meet its metabolic needs. Tumors take up cholesterol from the blood stream through their vasculature. Breast cancer grows in, and ovarian cancer metastasizes into fatty tissue that provides them with an additional source of cholesterol. High levels of extracellular cholesterol are beneficial for tumors whose cancer cells master the uptake of extracellular cholesterol. In this review we concentrate on cholesterol uptake mechanisms, receptor-mediated endocytosis and macropinocytosis, and how these are utilized and manipulated by cancer cells to overcome their possible intrinsic or pharmacological limitations in cholesterol synthesis. We focus especially on the involvement of lysosomes in cholesterol uptake. Identifying the vulnerabilities of cholesterol metabolism and manipulating them could provide novel efficient therapeutic strategies for treatment of cancers that manifest dependency for extracellular cholesterol.
Asunto(s)
Neoplasias de la Mama , Colesterol , Neoplasias Ováricas , Humanos , Colesterol/metabolismo , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Femenino , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , AnimalesRESUMEN
Aquaporin-0 (AQP0) tetramers form square arrays in lens membranes through a yet unknown mechanism, but lens membranes are enriched in sphingomyelin and cholesterol. Here, we determined electron crystallographic structures of AQP0 in sphingomyelin/cholesterol membranes and performed molecular dynamics (MD) simulations to establish that the observed cholesterol positions represent those seen around an isolated AQP0 tetramer and that the AQP0 tetramer largely defines the location and orientation of most of its associated cholesterol molecules. At a high concentration, cholesterol increases the hydrophobic thickness of the annular lipid shell around AQP0 tetramers, which may thus cluster to mitigate the resulting hydrophobic mismatch. Moreover, neighboring AQP0 tetramers sandwich a cholesterol deep in the center of the membrane. MD simulations show that the association of two AQP0 tetramers is necessary to maintain the deep cholesterol in its position and that the deep cholesterol increases the force required to laterally detach two AQP0 tetramers, not only due to protein-protein contacts but also due to increased lipid-protein complementarity. Since each tetramer interacts with four such 'glue' cholesterols, avidity effects may stabilize larger arrays. The principles proposed to drive AQP0 array formation could also underlie protein clustering in lipid rafts.
Asunto(s)
Acuaporinas , Colesterol , Microdominios de Membrana , Simulación de Dinámica Molecular , Esfingomielinas , Colesterol/metabolismo , Colesterol/química , Acuaporinas/química , Acuaporinas/metabolismo , Microdominios de Membrana/metabolismo , Microdominios de Membrana/química , Esfingomielinas/química , Esfingomielinas/metabolismo , Animales , Proteínas del Ojo/química , Proteínas del Ojo/metabolismo , Multimerización de Proteína , Cristalino/química , Cristalino/metabolismo , Conformación ProteicaRESUMEN
Paired immunoglobin-like type 2 receptor beta (PILRB) mainly plays a crucial role in regulating innate immunity, but whether PILRB is involved in cancer is poorly understood. Here, we report that PILRB potentiates the PI3K/AKT pathway to drive gastric tumorigenesis by binding and stabilizing IRS4, which could hyperactivate the PI3K/AKT pathway. Firstly, the levels of PILRB are upregulated in human gastric cancer (GC) specimens and associated with poor prognosis in patients with GC. In addition, our data show that PILRB promotes cell proliferation, colony formation, cell migration and invasion in GC cells in vitro and in vivo. Mechanistically, PILRB recruits the deubiquitination enzymes OTUB1 to IRS4 and relieves K48-linked ubiquitination of IRS4, protecting IRS4 protein from proteasomal-mediated degradation and subsequent activation of the PI3K/AKT pathway. Importantly, the levels of PILRB are positively correlated with IRS4 in GC specimens. Meanwhile, we also found that PILRB reprogrammed cholesterol metabolism by altering ABCA1 and SCARB1 expression levels, and PILRB-expression confers GC cell resistance to statin treatment. Taken together, our findings illustrate that the oncogenic role of PILRB in gastric tumorigenesis, providing new insights into the regulation of PI3K/AKT signaling in GC and establishing PILRB as a biomarker for simvastatin therapy resistance in GC.
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Carcinogénesis , Colesterol , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patología , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Animales , Colesterol/metabolismo , Carcinogénesis/metabolismo , Carcinogénesis/patología , Carcinogénesis/genética , Línea Celular Tumoral , Ratones , Ratones Desnudos , Proliferación Celular , Metástasis de la Neoplasia , Movimiento Celular , Masculino , Ratones Endogámicos BALB CRESUMEN
Changes in dietary patterns and living habits have led to an increasing number of individuals with elevated cholesterol levels. Excessive consumption of high-cholesterol foods can disrupt the body's lipid metabolism. Numerous studies have firmly established the cholesterol-lowering effects of probiotics and prebiotics, with evidence showing that the synergistic use of synbiotics is functionally more potent than using probiotics or prebiotics alone. Currently, the screening strategy involves screening prebiotics for synbiotic development with probiotics as the core. However, in comparison to probiotics, there are fewer types of prebiotics available, leading to limited resources. Consequently, the combinations of synbiotics obtained are restricted, and probiotics and prebiotics are only relatively suitable. Therefore, in this study, a novel synbiotic screening strategy with prebiotics as the core was developed. The synbiotic combination of Lactobacillus rhamnosus S_82 and xylo-oligosaccharides was screened from the intestinal tract of young people through five generations of xylo-oligosaccharides. Subsequently, the cholesterol-lowering ability of the medium was simulated, and the two carbon sources of glucose and xylo-oligosaccharides were screened out. The results showed that synbiotics may participate in cholesterol-lowering regulation by down-regulating the expression of NPC1L1 gene, down-regulating ACAT2 and increasing the expression of ABCG8 gene in vitro through cell adsorption and cell absorption in vitro, and regulating the intestinal microbiota. Synbiotics hold promise as potential candidates for the prevention of hypercholesterolemia in humans and animals, and this study providing a theoretical foundation for the development of new synbiotic products.
Asunto(s)
Lacticaseibacillus rhamnosus , Oligosacáridos , Prebióticos , Simbióticos , Lacticaseibacillus rhamnosus/metabolismo , Oligosacáridos/farmacología , Humanos , Hipolipemiantes/farmacología , Colesterol/metabolismo , Colesterol/sangre , Microbioma Gastrointestinal/efectos de los fármacos , Probióticos , GlucuronatosRESUMEN
Visceral cestodiases, like cysticercoses and echinococcoses, are caused by cystic larvae from parasites of the Cestoda class and are endemic or hyperendemic in many areas of the world. Current therapeutic approaches for these diseases are complex and present limitations and risks. Therefore, new safer and more effective treatments are urgently needed. The Niemann-Pick C1 (NPC1) protein is a cholesterol transporter that, based on genomic data, would be the solely responsible for cholesterol uptake in cestodes. Considering that human NPC1L1 is a known target of ezetimibe, used in the treatment of hypercholesterolemia, it has the potential for repurposing for the treatment of visceral cestodiases. Here, phylogenetic, selective pressure and structural in silico analyses were carried out to assess NPC1 evolutive and structural conservation, especially between cestode and human orthologs. Two NPC1 orthologs were identified in cestode species (NPC1A and NPC1B), which likely underwent functional divergence, leading to the loss of cholesterol transport capacity in NPC1A. Comparative interaction analyses performed by molecular docking of ezetimibe with human NPC1L1 and cestode NPC1B pointed out to similarities that consolidate the idea of cestode NPC1B as a target for the repurposing of ezetimibe as a drug for the treatment of visceral cestodiases.
Asunto(s)
Cestodos , Ezetimiba , Proteína Niemann-Pick C1 , Ezetimiba/farmacología , Ezetimiba/uso terapéutico , Humanos , Animales , Proteína Niemann-Pick C1/metabolismo , Cestodos/metabolismo , Cestodos/efectos de los fármacos , Cestodos/genética , Filogenia , Simulación del Acoplamiento Molecular , Reposicionamiento de Medicamentos/métodos , Simulación por Computador , Colesterol/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Proteínas de Transporte de Membrana/química , Proteínas de Transporte de Membrana/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/química , Anticolesterolemiantes/farmacología , Anticolesterolemiantes/uso terapéuticoRESUMEN
BACKGROUND: Cervical cancer, encompassing squamous cell carcinoma and endocervical adenocarcinoma (CESC), presents a considerable risk to the well-being of women. Recent studies have reported that squalene epoxidase (SQLE) is overexpressed in several cancers, which contributes to cancer development. METHODS: RNA sequencing data for SQLE were obtained from The Cancer Genome Atlas. In vitro experiments, including colorimetry, colony formation, Transwell, RT-qPCR, and Western blotting were performed. Furthermore, a transplanted CESC nude mouse model was constructed to validate the tumorigenic activity of SQLE in vivo. Associations among the SQLE expression profiles, differentially expressed genes (DEGs), immune infiltration, and chemosensitivity were examined. The prognostic value of genetic changes and DNA methylation in SQLE were also assessed. RESULTS: SQLE mRNA expression was significantly increased in CESC. ROC analysis revealed the strong diagnostic ability of SQLE toward CESC. Patients with high SQLE expression experienced shorter overall survival. The promotional effects of SQLE on cancer cell proliferation, metastasis, cholesterol synthesis, and EMT were emphasized. DEGs functional enrichment analysis revealed the signaling pathways and biological processes. Notably, a connection existed between the SQLE expression and the presence of immune cells as well as the activation of immune checkpoints. Increased SQLE expressions exhibited increased chemotherapeutic responses. SQLE methylation status was significantly associated with CESC prognosis. CONCLUSION: SQLE significantly affects CESC prognosis, malignant behavior, cholesterol synthesis, EMT, and immune infiltration; thereby offering diagnostic and indicator roles in CESC. Thus, SQLE can be a novel therapeutic target in CESC treatment.
Asunto(s)
Biomarcadores de Tumor , Colesterol , Transición Epitelial-Mesenquimal , Escualeno-Monooxigenasa , Neoplasias del Cuello Uterino , Humanos , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/inmunología , Neoplasias del Cuello Uterino/mortalidad , Femenino , Transición Epitelial-Mesenquimal/genética , Animales , Pronóstico , Escualeno-Monooxigenasa/genética , Escualeno-Monooxigenasa/metabolismo , Ratones , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Colesterol/metabolismo , Ratones Desnudos , Regulación Neoplásica de la Expresión Génica , Metilación de ADN , Línea Celular Tumoral , Proliferación Celular , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/inmunología , Adenocarcinoma/genética , Adenocarcinoma/patología , Adenocarcinoma/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismoRESUMEN
Grape seed proanthocyanidin extract (GSPE) is a natural polyphenolic compound, which plays an important role in anti-inflammatory and antioxidant. The present study aimed to investigate the effects of GSPE supplementation on the cholesterol metabolism and antioxidant status of finishing pigs. In longissimus dorse (LD) muscle, the data showed that GSPE significantly decreased the contents of total cholesterol (T-CHO) and triglyceride (TG), and decreased the mRNA expression of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoAR) and Fatty acid synthase (FAS), while increased the mRNA expression of carnitine palmitoyl transferase-1b (CPT1b), peroxisome proliferator-activated receptors (PPARα) and peroxisome proliferator activated receptor-γ coactivator-1α (PGC-1α). GSPE also reduced the enzyme activities of HMG-CoAR and FAS, and meanwhile amplified the activity of CPT1b in LD muscle of finishing pigs. Furthermore, dietary GSPE supplementation increased the serum catalase (CAT) and total antioxidant capacity (T-AOC), serum and liver total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) levels, while reduced serum and liver malondialdehyde (MDA) level in finishing pigs. In the liver, Superoxide Dismutase 1 (SOD1), catalase (CAT), glutathione peroxidase 1 (GPX1), Nuclear Factor erythroid 2-Related Factor 2 (NRF2) mRNA levels were increased by GSPE. In conclusion, this study showed that GSPE might be an effective dietary supplement for improving cholesterol metabolism and antioxidant status in finishing pigs.
Asunto(s)
Antioxidantes , Colesterol , Extracto de Semillas de Uva , Proantocianidinas , Animales , Proantocianidinas/farmacología , Extracto de Semillas de Uva/farmacología , Antioxidantes/metabolismo , Antioxidantes/farmacología , Colesterol/sangre , Colesterol/metabolismo , Porcinos , Suplementos Dietéticos , Hígado/metabolismo , Hígado/efectos de los fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/efectos de los fármacos , Carnitina O-Palmitoiltransferasa/metabolismo , Carnitina O-Palmitoiltransferasa/genéticaRESUMEN
Obsessive-Compulsive Disorder (OCD) poses a multifaceted challenge in psychiatry, with various subtypes and severities greatly impacting well-being. Recent scientific attention has turned towards lipid metabolism, particularly the neurolipidome, in response to clinical demands for cost-effective diagnostics and therapies. This scoping review integrates recent animal, translational, and clinical studies to explore impaired neurolipid metabolism mechanisms in OCD's pathogenesis, aiming to enhance future diagnostics and therapeutics. Five key neurolipids - endocannabinoids, lipid peroxidation, phospholipids, cholesterol, and fatty acids - were identified as relevant. While the endocannabinoid system shows promise in animal models, its clinical application remains limited. Conversely, lipid peroxidation and disruptions in phospholipid metabolism exhibit significant impacts on OCD's pathophysiology based on robust clinical data. However, the role of cholesterol and fatty acids remains inconclusive. The review emphasises the importance of translational research in linking preclinical findings to real-world applications, highlighting the potential of the neurolipidome as a potential biomarker for OCD detection and monitoring. Further research is essential for advancing OCD understanding and treatment modalities.
Asunto(s)
Trastorno Obsesivo Compulsivo , Trastorno Obsesivo Compulsivo/metabolismo , Trastorno Obsesivo Compulsivo/diagnóstico , Trastorno Obsesivo Compulsivo/terapia , Humanos , Animales , Metabolismo de los Lípidos/fisiología , Endocannabinoides/metabolismo , Ácidos Grasos/metabolismo , Fosfolípidos/metabolismo , Colesterol/metabolismo , Peroxidación de Lípido/fisiologíaRESUMEN
Transitions between the fed and fasted state are common in mammals. The liver orchestrates adaptive responses to feeding/fasting by transcriptionally regulating metabolic pathways of energy usage and storage. Transcriptional and enhancer dynamics following cessation of fasting (refeeding) have not been explored. We examined the transcriptional and chromatin events occurring upon refeeding in mice, including kinetic behavior and molecular drivers. We found that the refeeding response is temporally organized with the early response focused on ramping up protein translation while the later stages of refeeding drive a bifurcated lipid synthesis program. While both the cholesterol biosynthesis and lipogenesis pathways were inhibited during fasting, most cholesterol biosynthesis genes returned to their basal levels upon refeeding while most lipogenesis genes markedly overshoot above pre-fasting levels. Gene knockout, enhancer dynamics, and ChIP-seq analyses revealed that lipogenic gene overshoot is dictated by LXRα. These findings from unbiased analyses unravel the mechanism behind the long-known phenomenon of refeeding fat overshoot.
Asunto(s)
Elementos de Facilitación Genéticos , Ayuno , Receptores X del Hígado , Hígado , Animales , Masculino , Ratones , Colesterol/metabolismo , Elementos de Facilitación Genéticos/genética , Ayuno/metabolismo , Regulación de la Expresión Génica , Lipogénesis , Hígado/metabolismo , Receptores X del Hígado/metabolismo , Receptores X del Hígado/genética , Ratones Endogámicos C57BL , Ratones NoqueadosRESUMEN
We reported previously that in preclinical models, BMP4 is a potent inhibitor of breast cancer metastasis and that high BMP4 protein levels predict favourable patient outcomes. Here, we analysed a breast cancer xenograft with or without enforced expression of BMP4 to gain insight into the mechanisms by which BMP4 suppresses metastasis. Transcriptomic analysis of cancer cells recovered from primary tumours and phosphoproteomic analyses of cancer cells exposed to recombinant BMP4 revealed that BMP4 inhibits cholesterol biosynthesis, with many genes in this biosynthetic pathway being downregulated by BMP4. The treatment of mice bearing low-BMP4 xenografts with a cholesterol-lowering statin partially mimicked the anti-metastatic activity of BMP4. Analysis of a cohort of primary breast cancers revealed a reduced relapse rate for patients on statin therapy if their tumours exhibited low BMP4 levels. These findings indicate that BMP4 may represent a predictive biomarker for the benefit of additional statin therapy in breast cancer patients.
Asunto(s)
Proteína Morfogenética Ósea 4 , Neoplasias de la Mama , Colesterol , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Humanos , Proteína Morfogenética Ósea 4/metabolismo , Proteína Morfogenética Ósea 4/genética , Femenino , Animales , Colesterol/biosíntesis , Colesterol/metabolismo , Ratones , Línea Celular Tumoral , Metástasis de la Neoplasia , Ensayos Antitumor por Modelo de Xenoinjerto , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacosRESUMEN
Dysfunction or loss of pancreatic ß cells can cause insulin deficiency and impaired glucose regulation, resulting in conditions like type 2 diabetes. The ATP-binding cassette transporter A1 (ABCA1) plays a key role in the reverse cholesterol transport system, and its decreased expression is associated with pancreatic ß cell lipotoxicity, resulting in abnormal insulin synthesis and secretion. Increased glutamate release can cause glucotoxicity in ß cells, though the detailed mechanisms remain unclear. This study investigated the effect of N-methyl-D-aspartic acid (NMDA) on ABCA1 expression in INS-1 cells and primary pancreatic islets to elucidate the signaling mechanisms that suppress insulin secretion. Using Western blotting, microscopy, and biochemical analyses, we found that NMDA activated the mitogen-activated protein kinase (MEK)-dependent pathway, suppressing ABCA1 protein and mRNA expression. The MEK-specific inhibitor PD98059 restored ABCA1 promoter activity, indicating the involvement of the extracellular signal-regulated kinase (MEK/ERK) pathway. Furthermore, we identified the liver X receptor (LXR) as an effector transcription factor in NMDA regulation of ABCA1 transcription. NMDA treatment increased cholesterol and triglyceride levels while decreasing insulin secretion, even under high-glucose conditions. These effects were abrogated by treatment with PD98059. This study reveals that NMDA suppresses ABCA1 expression via the MEK/ERK/LXR pathway, providing new insights into the pathological suppression of insulin secretion in pancreatic ß cells and emphasizing the importance of investigating the role of NMDA in ß cell dysfunction.
Asunto(s)
Transportador 1 de Casete de Unión a ATP , Células Secretoras de Insulina , Receptores X del Hígado , Sistema de Señalización de MAP Quinasas , N-Metilaspartato , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/efectos de los fármacos , Animales , Transportador 1 de Casete de Unión a ATP/metabolismo , Transportador 1 de Casete de Unión a ATP/genética , N-Metilaspartato/farmacología , Ratas , Receptores X del Hígado/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Colesterol/metabolismo , Insulina/metabolismo , Secreción de Insulina/efectos de los fármacos , Masculino , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Línea CelularRESUMEN
Frizzleds (ten paralogs: FZD1-10) belong to the class F of G protein-coupled receptors (GPCRs), which remains poorly understood despite its crucial role in multiple key biological functions including embryonic development, stem cell regulation, and homeostasis in the adult. FZD7, one of the most studied members of the family, is more specifically involved in the migration of mesendoderm cells during the development and renewal of intestinal stem cells in adults. Moreover, FZD7 has been highlighted for its involvement in tumor development predominantly in the gastrointestinal tract. This study reports the structure of inactive FZD7, without any stabilizing mutations, determined by cryo-electron microscopy (cryo-EM) at 1.9 Å resolution. We characterize a fluctuating water pocket in the core of the receptor important for FZD7 dynamics. Molecular dynamics simulations are used to investigate the temporal distribution of those water molecules and their importance for potential conformational changes in FZD7. Moreover, we identify lipids interacting with the receptor core and a conserved cholesterol-binding site, which displays a key role in FZD7 association with a transducer protein, Disheveled (DVL), and initiation of downstream signaling and signalosome formation.
Asunto(s)
Microscopía por Crioelectrón , Receptores Frizzled , Simulación de Dinámica Molecular , Humanos , Regulación Alostérica , Sitios de Unión , Colesterol/metabolismo , Colesterol/química , Receptores Frizzled/metabolismo , Receptores Frizzled/química , Receptores Frizzled/genética , Células HEK293 , Unión ProteicaAsunto(s)
Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1 , Colesterol , Colesterol/metabolismo , Colesterol/biosíntesis , Animales , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1/genética , Humanos , Glándulas Suprarrenales/metabolismo , Esteroides/biosíntesis , Esteroides/metabolismo , RatonesRESUMEN
Most patients with schizophrenia (SCZ) do not exhibit violent behaviors and are more likely to be victims rather than perpetrators of violent acts. However, a subgroup of forensic detainees with SCZ exhibit tendencies to engage in criminal violations. Although numerous models have been proposed, ranging from substance use, serotonin transporter gene, and cognitive dysfunction, the molecular underpinnings of violence in SCZ patients remains elusive. Lithium and clozapine have established anti-aggression properties and recent studies have linked low cholesterol levels and ultraviolet (UV) radiation with human aggression, while vitamin D3 reduces violent behaviors. A recent study found that vitamin D3, omega-3 fatty acids, magnesium, and zinc lower aggression in forensic population. In this review article, we take a closer look at aryl hydrocarbon receptor (AhR) and the dysfunctional lipidome in neuronal membranes, with emphasis on cholesterol and vitamin D3 depletion, as sources of aggressive behavior. We also discuss modalities to increase the fluidity of neuronal double layer via membrane lipid replacement (MLR) and natural or synthetic compounds. This article is part of the Special Issue on "Personality Disorders".
Asunto(s)
Antipsicóticos , Esquizofrenia , Humanos , Esquizofrenia/metabolismo , Antipsicóticos/uso terapéutico , Colesterol/metabolismo , Animales , Colecalciferol/metabolismo , Agresión/fisiología , Agresión/efectos de los fármacosRESUMEN
Niemann-Pick disease type C (NPC) is a rare and fatal neurological disorder caused by mutations in Npc1 or Npc2, with Npc1 accounting for 95% of cases. These mutations result in the functional loss of their respective proteins, causing cellular abnormalities characterized by disrupted lipid dysregulation, calcium dysfunction, elevated damage associated molecular patterns (DAMPs), and a pro-inflammatory environment. This cellular pathology ultimately triggers neurodegeneration, with the cerebellum being the earliest and most affected region. We have recently shown atypical activation of interferon signaling in the presymptomatic Npc1-/- mouse cerebellum and, to a lesser extent, in the cerebral cortex. In addition, we reported that the Amyloid Precursor Protein (APP) is an NPC disease modifier. Loss of APP function leads to widespread neurodegeneration in the NPC brain, including exacerbated interferon signaling in the cerebellum. To better understand the role of APP as a disease modifier throughout the NPC brain, here we carried out a transcriptomic analysis of the cerebral cortex and cerebellum from 3-week-old Npc1-/- mice as well as age-matched controls in the presence and absence of APP. We report differential effects of APP loss of function in the cerebral cortex and cerebellum, including cholesterol and tau dysregulation, in both brain regions. Our findings demonstrate a novel link between APP loss and early pathogenic mechanisms in NPC.
Asunto(s)
Precursor de Proteína beta-Amiloide , Cerebelo , Colesterol , Homeostasis , Interferones , Proteína Niemann-Pick C1 , Enfermedad de Niemann-Pick Tipo C , Transducción de Señal , Proteínas tau , Animales , Enfermedad de Niemann-Pick Tipo C/metabolismo , Enfermedad de Niemann-Pick Tipo C/genética , Enfermedad de Niemann-Pick Tipo C/patología , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Ratones , Proteínas tau/metabolismo , Proteínas tau/genética , Colesterol/metabolismo , Fosforilación , Cerebelo/metabolismo , Cerebelo/patología , Interferones/metabolismo , Interferones/genética , Corteza Cerebral/metabolismo , Corteza Cerebral/patología , Ratones Noqueados , Modelos Animales de EnfermedadRESUMEN
Inflammation plays a critical role in the development of numerous diseases. Cannabidiol (CBD), found in hemp, exhibits significant pharmacological activities. Accumulating evidence suggests that CBD has anti-inflammatory and cardiovascular protection effects, but the potential mechanisms require further exploration. In this study, we aimed to reveal the mechanisms of CBD against high-fat, high-cholesterol (HFC) diet-induced inflammation combining metabolomics with network pharmacology. First, plasma lipidomics results indicated that oxidized lipids could serve as potential biomarkers for HFC diet-induced inflammation, and CBD reversed the elevated levels of oxidized lipids. The HFC diet was also found to enhance intestinal permeability, facilitating the entry of lipopolysaccharides (LPSs) into the circulatory system and subsequently increasing systemic inflammation. Additionally, cell metabolomic results indicated that CBD could reverse 10 important differential metabolites in LPS-induced RAW 264.7 cells. Using network pharmacology, we identified 49 core targets, and enrichment analysis revealed that arachidonic acid was the most significantly affected by CBD, which was closely associated with inflammation. Further integrated analysis focused on three key targets, including PTGS2, ALOX5, and ALOX15. Molecular docking showed high affinities between key targets and CBD, and qPCR further demonstrated that CBD could reverse the mRNA expression of these key targets in RAW 264.7 cells. Collectively, this finding integrates lipidomics and metabolomics with network pharmacology to elucidate the anti-inflammatory effects of CBD and validates key therapeutic targets.
Asunto(s)
Antiinflamatorios , Cannabidiol , Dieta Alta en Grasa , Inflamación , Lipidómica , Metabolómica , Ratones Endogámicos C57BL , Farmacología en Red , Animales , Cannabidiol/farmacología , Ratones , Dieta Alta en Grasa/efectos adversos , Inflamación/metabolismo , Inflamación/tratamiento farmacológico , Masculino , Antiinflamatorios/farmacología , Antiinflamatorios/química , Células RAW 264.7 , Humanos , Colesterol/metabolismo , Simulación del Acoplamiento Molecular , Araquidonato 5-Lipooxigenasa/metabolismo , Araquidonato 5-Lipooxigenasa/genética , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismoRESUMEN
Drugs that lower plasma apolipoprotein B (ApoB)-containing lipoproteins are central to treating advanced atherosclerosis and provide partial protection against clinical events. Previous research showed that lowering ApoB-containing lipoproteins stops plaque inflammation, but how these drugs affect the heterogeneous population of plaque cells derived from smooth muscle cells (SMCs) is unknown. SMC-derived cells are the main cellular component of atherosclerotic lesions and the source of structural components that determine the size of plaques and their propensity to rupture and trigger thrombosis, the proximate cause of heart attack and stroke. Using lineage tracing and single-cell techniques to investigate the full SMC-derived cellular compartment in progressing and regressing plaques in mice, here we show that lowering ApoB-containing lipoproteins reduces nuclear factor kappa-light-chain-enhancer of activated B cells signaling in SMC-derived fibromyocytes and chondromyocytes and leads to depletion of these abundant cell types from plaques. These results uncover an important mechanism through which cholesterol-lowering drugs can achieve plaque regression.
Asunto(s)
Aterosclerosis , Modelos Animales de Enfermedad , Miocitos del Músculo Liso , Placa Aterosclerótica , Animales , Placa Aterosclerótica/patología , Placa Aterosclerótica/metabolismo , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/patología , Miocitos del Músculo Liso/metabolismo , Aterosclerosis/patología , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/metabolismo , Condrocitos/efectos de los fármacos , Condrocitos/patología , Condrocitos/metabolismo , Transducción de Señal/efectos de los fármacos , Ratones Endogámicos C57BL , Anticolesterolemiantes/farmacología , Anticolesterolemiantes/uso terapéutico , Masculino , Colesterol/metabolismo , Colesterol/sangre , Ratones , Enfermedades de la Aorta/patología , Enfermedades de la Aorta/metabolismo , Análisis de la Célula Individual , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/patología , Músculo Liso Vascular/metabolismo , FN-kappa B/metabolismoRESUMEN
Osteoclasts are multinucleated bone-resorbing cells, and their formation is tightly regulated to prevent excessive bone loss. However, the mechanisms by which osteoclast formation is restricted remain incompletely determined. Here, we found that sterol regulatory element binding protein 2 (SREBP2) functions as a negative regulator of osteoclast formation and inflammatory bone loss. Cholesterols and SREBP2, a key transcription factor for cholesterol biosynthesis, increased in the late phase of osteoclastogenesis. The ablation of SREBP2 in myeloid cells resulted in increased in vivo and in vitro osteoclastogenesis, leading to low bone mass. Moreover, deletion of SREBP2 accelerated inflammatory bone destruction in murine inflammatory osteolysis and arthritis models. SREBP2-mediated regulation of osteoclastogenesis is independent of its canonical function in cholesterol biosynthesis but is mediated, in part, by its downstream target, interferon regulatory factor 7 (IRF7). Taken together, our study highlights a previously undescribed role of the SREBP2-IRF7 regulatory circuit as a negative feedback loop in osteoclast differentiation and represents a novel mechanism to restrain pathological bone destruction.
Asunto(s)
Diferenciación Celular , Factor 7 Regulador del Interferón , Osteoclastos , Proteína 2 de Unión a Elementos Reguladores de Esteroles , Animales , Osteoclastos/metabolismo , Proteína 2 de Unión a Elementos Reguladores de Esteroles/metabolismo , Proteína 2 de Unión a Elementos Reguladores de Esteroles/genética , Ratones , Factor 7 Regulador del Interferón/metabolismo , Factor 7 Regulador del Interferón/genética , Inflamación/metabolismo , Inflamación/patología , Ratones Endogámicos C57BL , Osteogénesis/fisiología , Resorción Ósea/metabolismo , Resorción Ósea/patología , Resorción Ósea/genética , Ratones Noqueados , Colesterol/metabolismoRESUMEN
Endoplasmic reticulum (ER)-endolysosome interactions regulate cholesterol exchange between the ER and the endolysosome. ER-endolysosome membrane contact sites mediate the ER-endolysosome interaction. VAP-ORP1L (vesicle-associated membrane protein-associated protein- OSBP-related protein 1L) interaction forms the major contact site between the ER and the lysosome, which is regulated by Rab7. RILP (Rab7-interacting lysosomal protein) is the downstream effector of Rab7, but its role in the organelle interaction between the ER and the lysosome is not clear. In this study, we found RILP interacts with ORP1L to competitively inhibit the formation of the VAP-ORP1L contact site. Immunofluorescence microscopy revealed that RILP induces late endosome/lysosome clustering, which reduces the contact of endolysosomes with the ER, interfering with the ER-endolysosome interaction. Further examination demonstrated that over-expression of RILP results in the accumulation of cholesterol in the clustered endolysosomes, which triggers cellular autophagy depending on RILP. Our results suggest that RILP interferes with the ER-endolysosome interaction to inhibit cholesterol flow from the endolysosome to the ER, which feedbacks to trigger autophagy.