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1.
Metabolites ; 14(4)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38668322

RESUMO

Inflammatory bowel disease (IBD) is multifactorial chronic inflammatory disease in the gastrointestinal tract, affecting patients' quality of life profoundly. The incidence of IBD has been on the rise globally for the last two decades. Because the molecular mechanisms underlying the disease remain not well understood, therapeutic development is significantly impeded. Metabolism is a crucial cellular process to generate the energy needed for an inflammatory response and tissue repair. Comprehensive understanding of the metabolic pathways in IBD would help to unravel the disease pathogenesis/progression and facilitate therapeutic discoveries. Here, we investigated four metabolic pathways altered in experimental colitis. C57BL/6J mice were treated with dextran sulfate sodium (DSS) in drinking water for 7 days to induce experimental ulcerative colitis (UC). We conducted proteomics analysis for the colon samples using LC/MS, to profile key metabolic intermediates. Our findings revealed significant alterations in four major metabolic pathways: antioxidative defense, ß-oxidation, glycolysis, and TCA cycle pathways. The energy metabolism by ß-oxidation, glycolysis, and TCA cycle pathways were downregulated under UC, together with reduced antioxidative defense pathways. These results reveal metabolic re-programming in intestinal cells under UC, showing dysregulation in all four major metabolic pathways. Our study underscores the importance of metabolic drivers in the pathogenesis of IBD and suggests that the modification of metabolism may serve as a novel diagnostic/therapeutic approach for IBD.

2.
Br J Pharmacol ; 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38679457

RESUMO

BACKGROUND AND PURPOSE: Chronic inflammation plays a pivotal role in the development of Type 2 diabetes mellitus (T2DM). Previous studies have shown that haem oxygenase-1 (HO-1) plays a proinflammatory role during metabolic stress, suggesting that HO-1 inhibition could be an effective strategy to treat T2DM. However, the application of HO-1 inhibitors is restricted due to solubility-limited bioavailability. In this study, we encapsulated the HO-1 inhibitor, zinc protoporphyrin IX (ZnPP), within nanoparticles and investigated their role in regulating glucose homeostasis and chronic inflammation during obesity. EXPERIMENTAL APPROACH: We delivered DMSO-dissolved ZnPP (DMSO-ZnPP) and ZnPP-laden nanoparticles (Nano-ZnPP) to diet-induced obese male mice for 6 weeks. Glucose and insulin tolerance tests were carried out, liver and adipose tissue gene expression profiles analysed, and systemic inflammation analysed using flow cytometry. KEY RESULTS: Nanoparticles significantly increased the delivery efficiency of ZnPP in both cells and mice. In mice with diet-induced obesity, inhibition of HO-1 by Nano-ZnPP significantly decreased adiposity, increased insulin sensitivity, and improved glucose tolerance. Moreover, Nano-ZnPP treatment attenuated both local and systemic inflammatory levels during obesity. Mechanistically, Nano-ZnPP significantly attenuated glucagon, TNF, and fatty acid synthesis signalling pathways in the liver. In white adipose tissue, the oxidative phosphorylation signalling pathway was enhanced and the inflammation signalling pathway diminished by Nano-ZnPP. Our results show that Nano-ZnPP has better effects on the improvement of glucose homeostasis and attenuation of chronic inflammation, than those of DMSO-dissolved ZnPP. CONCLUSIONS AND IMPLICATIONS: These findings indicate that ZnPP-laden nanoparticles are potential therapeutic agents for treating T2DM.

3.
Geroscience ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38462569

RESUMO

Obesity and exercise intolerance greatly reduce the life quality of older people. Prolyl hydroxylase domain-containing protein 2 (PHD2) is an important enzyme in modulating hypoxia-inducible factor-alpha (HIF) protein. Using vascular endothelial cell-specific PHD2 gene knockout (PHD2 ECKO) mice, we investigated the role of endothelial PHD2 in aging-related obesity and exercise capacity. Briefly, PHD2 ECKO mice were obtained by crossing PHD2-floxed mice with VE-Cadherin (Cdh5)-Cre transgenic mice. The effect of PHD2 ECKO on obesity and exercise capacity in PHD2 ECKO mice and control PHD2f/f mice were determined in young mice (6 to 7 months) and aged mice (16-18 months). We found that aged PHD2 ECKO mice, but not young mice, exhibited a lean phenotype, characterized by lower fat mass, and its ratio to lean weight, body weight, or tibial length, while their food uptake was not reduced compared with controls. Moreover, as compared with aged control mice, aged PHD2 ECKO mice exhibited increased oxygen consumption at rest and during exercise, and the maximum rate of oxygen consumption (VO2 max) during exercise. Furthermore, as compared with corresponding control mice, both young and aged PHD2 ECKO mice demonstrated improved glucose tolerance and lower insulin resistance. Together, these data demonstrate that inhibition of vascular endothelial PHD2 signaling significantly attenuates aging-related obesity, exercise intolerance, and glucose intolerance.

4.
Front Immunol ; 15: 1339937, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464534

RESUMO

Obesity is associated with chronic inflammation in the central nervous system (CNS), and neuroinflammation has been shown to have detrimental effects on mood and cognition. The growth hormone secretagogue receptor (GHSR), the biologically relevant receptor of the orexigenic hormone ghrelin, is primarily expressed in the brain. Our previous study showed that neuronal GHSR deletion prevents high-fat diet-induced obesity (DIO). Here, we investigated the effect of neuronal GHSR deletion on emotional and cognitive functions in DIO. The neuron-specific GHSR-deficient mice exhibited reduced depression and improved spatial memory compared to littermate controls under DIO. We further examined the cortex and hippocampus, the major regions regulating cognitive and emotional behaviors, and found that the neuronal deletion of GHSR reduced DIO-induced neuroinflammation by suppressing proinflammatory chemokines/cytokines and decreasing microglial activation. Furthermore, our data showed that neuronal GHSR deletion suppresses neuroinflammation by downregulating AMPK-autophagy signaling in neurons. In conclusion, our data reveal that neuronal GHSR inhibition protects against DIO-induced depressive-like behavior and spatial cognitive dysfunction, at least in part, through AMPK-autophagy signaling-mediated neuroinflammation.


Assuntos
Proteínas Quinases Ativadas por AMP , Receptores de Grelina , Animais , Camundongos , Depressão/genética , Dieta Hiperlipídica/efeitos adversos , Inflamação/complicações , Doenças Neuroinflamatórias , Neurônios , Obesidade/complicações , Receptores de Grelina/genética
5.
Int J Biol Macromol ; 262(Pt 1): 129974, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38331068

RESUMO

Mitochondria in breast cancer play a critical role in survival and adaptation to dynamic environments. Thus, targeting mitochondria emerges as a promising therapeutic strategy for breast cancer. However, the adaptive unfolded protein response in mitochondria (UPRmt) due to mitochondrial unspecific distribution might contribute to diminished therapeutic outcomes. Herein, mitochondrial targeting liposome agents (CTPP-Lipid) are constructed and adopted for delivering the copper ion (CuET-DSF), which is especially sensitive for mitochondria-abundant breast tumors. In brief, the CTPP-Lipid@CuET achieves the goal of Cu2+ overloading by mitochondria targeting delivery. This rapidly increases ROS production, disrupts mitochondrial structure, and avoids the adaptive UPRmt formation, finally leading to apoptosis of breast cancer cells. In general, the Cu2+ overloading at mitochondria by CTPP-Lipid@CuET is a potential strategy for antitumor therapy, providing new insights into breast tumor therapy.


Assuntos
Neoplasias da Mama , Lipossomos , Humanos , Feminino , Cobre/farmacologia , Neoplasias da Mama/tratamento farmacológico , Resposta a Proteínas não Dobradas , Lipídeos
6.
Colloids Surf B Biointerfaces ; 236: 113799, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367290

RESUMO

Inflammatory bowel disease (IBD) remains a global health concern with a complex and incompletely understood pathogenesis. In the course of IBD development, damage to intestinal epithelial cells and a reduction in the expression of tight junction (TJ) proteins compromise the integrity of the intestinal barrier, exacerbating inflammation. Notably, the renin-angiotensin system and angiotensin II receptor type 1 (AT1R) play a crucial role in regulating the pathological progression including vascular permeability, and immune microenvironment. Thus, Telmisartan (Tel), an AT1R inhibitor, loading thermosensitive hydrogel was constructed to investigate the potential of alleviating inflammatory bowel disease through rectal administration. The constructed hydrogel exhibits an advantageous property of rapid transformation from a solution to a gel state at 37°C, facilitating prolonged drug retention within the gut while mitigating irritation associated with rectal administration. Results indicate that Tel also exhibits a beneficial effect in ameliorating colon shortening, colon wall thickening, cup cell lacking, crypt disappearance, and inflammatory cell infiltration into the mucosa in colitis mice. Moreover, it significantly upregulates the expression of TJ proteins in colonic tissues thereby repairing the intestinal barrier damage and alleviating the ulcerative colitis (UC) disease process. In conclusion, Tel-loaded hydrogel demonstrates substantial promise as a potential treatment modality for IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Camundongos , Animais , Telmisartan/farmacologia , Telmisartan/metabolismo , Hidrogéis/farmacologia , Mucosa Intestinal/metabolismo , Junções Íntimas/metabolismo , Junções Íntimas/patologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/patologia , Colite/patologia , Colo/metabolismo , Inflamação/metabolismo , Sulfato de Dextrana/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
8.
Materials (Basel) ; 17(2)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38255441

RESUMO

Theoretical analysis indicated that partially deuterated ammonium dihydrogen phosphate (DADP) crystal with a deuterium content of 23% could realize spectral noncritical phase-matching (S-NCPM) for type-I frequency doubling of an Nd:glass laser. To explore the temperature dependence of the phase matching (PM) angle of the second harmonic generation (SHG) process and the output SHG bandwidth of DADP crystal at 1.053 µm, we used the point-seed rapid-growth method to grow targeted DADP crystal with 23% deuterium content. Experimental results indicated that the grown DADP crystal had high quality and large dimensions (7 × 6 × 6 cm3). Using a femtosecond OPO laser as a tunable light source, the temperature dependence of the PM angle of the SHG process in DADP crystal at 1.053 µm was investigated. The PM angle changed linearly with temperature, as predicted by the theoretical calculation. In addition, under the condition of higher temperature, broad bandwidths of the second harmonic of DADP crystal were still observed. These results provide excellent guidance and reference value for the application of wavelength insensitive phase-matched second harmonic generation in partially deuterated DADP.

10.
J Nanobiotechnology ; 22(1): 12, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38166896

RESUMO

Ceria nanoparticles (CeO2NPs) exhibit great potential in cardiovascular disease and nonalcoholic fatty liver disease due to its excellent antioxidant capacity. However, the profitable effect of CeO2NPs on many diseases is almost all attributed to the regulation of ROS. Apart from the general antioxidant function, there seems to be no more distinct mechanism to reflect its unique multi-disease improvement effect. Here, we for the first time reveal a new discovery of CeO2NPs in mimicking nitric oxide synthase (NOS) by catalyzing L-arginine (L-Arg) to produce nitric oxide (NO) or the derivatives. NOS-like activity of CeO2NPs is original and associated with multiple factors like substrate concentration, pH, temperature and time, etc. where oxygen vacancy ratio plays a more critical role. Meanwhile, NOS-like activity of CeO2NPs successfully elevates NO secretion in endothelial cells and macrophages without expanding eNOS/iNOS expression. Importantly, NOS-like activity of CeO2NPs and the responsive endogenous NO promote the re-distribution of blood lipids and stabilize eNOS expression but suppress iNOS, thus collectively alleviate the accumulation of vascular plaque. Altogether, we provide a new angle of view to survey the outstanding potential of CeO2NPs, apart from the inevitable antioxidant capacity, the covert but possible and more critical NOS-like enzymatic activity is more noteworthy.


Assuntos
Antioxidantes , Células Endoteliais , Nanopartículas , Óxido Nítrico Sintase , Placa Aterosclerótica , Antioxidantes/metabolismo , Arginina/metabolismo , Células Endoteliais/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Nanopartículas/química
11.
Mol Metab ; 79: 101852, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38092245

RESUMO

OBJECTIVE: Obesity-associated chronic inflammation, aka meta-inflammation, is a key pathogenic driver for obesity-associated comorbidity. Growth hormone secretagogue receptor (GHSR) is known to mediate the effects of nutrient-sensing hormone ghrelin in food intake and fat deposition. We previously reported that global Ghsr ablation protects against diet-induced inflammation and insulin resistance, but the site(s) of action and mechanism are unknown. Macrophages are key drivers of meta-inflammation. To unravel the role of GHSR in macrophages, we generated myeloid-specific Ghsr knockout mice (LysM-Cre;Ghsrf/f). METHODS: LysM-Cre;Ghsrf/f and control Ghsrf/f mice were subjected to 5 months of high-fat diet (HFD) feeding to induce obesity. In vivo, metabolic profiling of food intake, physical activity, and energy expenditure, as well as glucose and insulin tolerance tests (GTT and ITT) were performed. At termination, peritoneal macrophages (PMs), epididymal white adipose tissue (eWAT), and liver were analyzed by flow cytometry and histology. For ex vivo studies, bone marrow-derived macrophages (BMDMs) were generated from the mice and treated with palmitic acid (PA) or lipopolysaccharide (LPS). For in vitro studies, macrophage RAW264.7 cells with Ghsr overexpression or Insulin receptor substrate 2 (Irs2) knockdown were studied. RESULTS: We found that Ghsr expression in PMs was increased under HFD feeding. In vivo, HFD-fed LysM-Cre;Ghsrf/f mice exhibited significantly attenuated systemic inflammation and insulin resistance without affecting food intake or body weight. Tissue analysis showed that HFD-fed LysM-Cre;Ghsrf/f mice have significantly decreased monocyte/macrophage infiltration, pro-inflammatory activation, and lipid accumulation, showing elevated lipid-associated macrophages (LAMs) in eWAT and liver. Ex vivo, Ghsr-deficient macrophages protected against PA- or LPS-induced pro-inflammatory polarization, showing reduced glycolysis, increased fatty acid oxidation, and decreased NF-κB nuclear translocation. At molecular level, GHSR metabolically programs macrophage polarization through PKA-CREB-IRS2-AKT2 signaling pathway. CONCLUSIONS: These novel results demonstrate that macrophage GHSR plays a key role in the pathogenesis of meta-inflammation, and macrophage GHSR promotes macrophage infiltration and induces pro-inflammatory polarization. These exciting findings suggest that GHSR may serve as a novel immunotherapeutic target for the treatment of obesity and its associated comorbidity.


Assuntos
Resistência à Insulina , Receptores de Grelina , Camundongos , Animais , Receptores de Grelina/genética , Receptores de Grelina/metabolismo , Resistência à Insulina/fisiologia , Lipopolissacarídeos/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , Camundongos Knockout , Obesidade/metabolismo , Nutrientes
12.
Apoptosis ; 29(1-2): 66-85, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37943371

RESUMO

Pyroptosis is a gasdermin-mediated programmed cell death (PCD) pathway. It differs from apoptosis because of the secretion of inflammatory molecules. Pyroptosis is closely associated with various malignant tumors. Recent studies have demonstrated that pyroptosis can either inhibit or promote the development of malignant tumors, depending on the cell type (immune or cancer cells) and duration and severity of the process. This review summarizes the molecular mechanisms of pyroptosis, its relationship with malignancies, and focuses on current pyroptosis inducers and their significance in cancer treatment. The molecules involved in the pyroptosis signaling pathway could serve as therapeutic targets for the development of novel drugs for cancer therapy. In addition, we analyzed the potential of combining pyroptosis with conventional anticancer techniques as a promising strategy for cancer treatment.


Assuntos
Neoplasias , Piroptose , Humanos , Apoptose , Transdução de Sinais , Neoplasias/tratamento farmacológico , Neoplasias/genética
13.
Cell Mol Gastroenterol Hepatol ; 17(1): 41-58, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37678798

RESUMO

BACKGROUND & AIMS: The O-class of the forkhead transcription factor FoxO1 is a crucial factor mediating insulin→PI3K→Akt signaling and governs diverse cellular processes. However, the role of hepatocyte FoxO1 in liver fibrosis has not been well-established. In his study, we investigated the role of hepatocyte FoxO1 in liver fibrosis and uncovered the underlying mechanisms. METHODS: Liver fibrosis was established by carbon tetrachloride (CCL4) administration and compared between liver-specific deletion of FoxO1 deletion (F1KO) and control (CNTR) mice. Using genetic and bioinformatic strategies in vitro and in vivo, the role of hepatic FoxO1 in liver fibrosis and associated mechanisms was established. RESULTS: Increased FoxO1 expression and FoxO1 signaling activation were observed in CCL4-induced fibrosis. Hepatic FoxO1 deletion largely attenuated CCL4-induced liver injury and fibrosis compared with CNTR mice. F1KO mice showed ameliorated CCL4-induced hepatic inflammation and decreased TGF-ß1 mRNA and protein levels compared with those of CNTR mice. In primary hepatocytes, FoxO1 deficiency reduced TGF-ß1 expression and secretion. Conditioned medium (CM) collected from wild-type hepatocytes treated with CCL4 activated human HSC cell line (LX-2); such effect was attenuated by FoxO1 deletion in primary hepatocytes or neutralization of TGF-ß1 in the CM using TGF-ß1 antibody. Hepatic FoxO1 overexpression in CNTR mice promoted CCL4-induced HSC activation; such effect was blocked in L-TGF-ß1KO mice. CONCLUSIONS: Hepatic FoxO1 mediates CCL4-inducled liver fibrosis via upregulating hepatocyte TGF-ß1 expression, stimulating hepatic inflammation and TGF-ß1-mediated HSC activation. Hepatic FoxO1 may be a therapeutic target for prevention and treatment of liver fibrosis.


Assuntos
Células Estreladas do Fígado , Fator de Crescimento Transformador beta1 , Animais , Humanos , Camundongos , Células Estreladas do Fígado/patologia , Hepatócitos/metabolismo , Inflamação/patologia , Cirrose Hepática/genética , Fator de Crescimento Transformador beta1/metabolismo
14.
Zhongguo Fei Ai Za Zhi ; 26(12): 889-900, 2024 Jan 02.
Artigo em Chinês | MEDLINE | ID: mdl-38151328

RESUMO

BACKGROUND: In China, lung cancer remains the cancer with the highest incidence and mortality rate. Among early-stage lung adenocarcinomas (LUAD), the micropapillary (MPP) component is prevalent and typically exhibits high aggressiveness, significantly correlating with early metastasis, lymphatic infiltration, and reduced five-year survival rates. Therefore, the study is to explore the similarities and differences between MPP and non-micropapillary (non-MPP) components in malignant pulmonary nodules characterized by GGOs in early-stage LUAD, identify unique mutational features of the MPP component and analyze the relationship between the ZNF469 gene, a member of the zinc-finger protein family, and the prognosis of early-stage LUAD, as well as its correlation with immune infiltration. METHODS: A total of 31 malignant pulmonary nodules of LUAD were collected and dissected into paired MPP and non-MPP components using microdissection. Whole-exome sequencing (WES) was performed on the components of early-stage malignant pulmonary nodules. Mutational signatures analysis was conducted using R packages such as maftools, Nonnegative Matrix Factorization (NMF), and Sigminer to unveil the genomic mutational characteristics unique to MPP components in invasive LUAD compared to other tumor tissues. Furthermore, we explored the expression of the ZNF469 gene in LUAD using The Cancer Genome Atlas (TCGA) database to investigate its potential association with the prognosis. We also investigated gene interaction networks and signaling pathways related to ZNF469 in LUAD using the GeneMANIA database and conducted Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Lastly, we analyzed the correlation between ZNF469 gene expression and levels of immune cell infiltration in LUAD using the TIMER and TISIDB databases. RESULTS: MPP components exhibited a higher number of genomic variations, particularly the 13th COSMIC (Catalogue of Somatic Mutations in Cancer) mutational signature characterized by the activity of the cytidine deaminase APOBEC family, which was unique to MPP components compared to non-MPP components in tumor tissues. This suggests the potential involvement of APOBEC in the progression of MPP components in early-stage LUAD. Additionally, MPP samples with high similarity to APOBEC signature displayed a higher tumor mutational burden (TMB), indicating that these patients may be more likely to benefit from immunotherapy. The expression of ZNF469 was significantly upregulated in LUAD compared to normal tissue, and was associated with poor prognosis in LUAD patients (P<0.05). Gene interaction network analysis and GO/KEGG enrichment analysis revealed that COL6A1, COL1A1, COL1A2, TGFB2, MMP2, COL8A2 and C2CD4C interacted with ZNF469 and were mainly involved in encoding collagen proteins and participating in the constitution of extracellular matrix. ZNF469 expression was positively correlated with immune cell infiltration in LUAD (P<0.05). CONCLUSIONS: The study has unveiled distinctive mutational signatures in the MPP components of early-stage invasive LUAD in the Asian population. Furthermore, we have identified that the elevated expression of mutated ZNF469 impacts the prognosis and immune infiltration in LUAD, suggesting its potential as a diagnostic and prognostic biomarker in LUAD.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/genética , Adenocarcinoma de Pulmão/genética , China , Prognóstico , Fatores de Transcrição
15.
bioRxiv ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38076894

RESUMO

The stomach-derived orexigenic hormone ghrelin is a key regulator of energy homeostasis and metabolism in humans. The ghrelin receptor, growth hormone secretagogue receptor 1a (GHSR), is widely expressed in the brain and gastrointestinal vagal sensory neurons, and neuronal GHSR knockout results in a profoundly beneficial metabolic profile and protects against diet-induced obesity (DIO) and insulin resistance. Here we show that in addition to the well characterized vagal GHSR, GHSR is robustly expressed in gastrointestinal sensory neurons emanating from spinal dorsal root ganglia. Remarkably, sensory neuron GHSR deletion attenuates DIO through increased energy expenditure and sympathetic outflow to adipose tissue independent of food intake. In addition, neuronal viral tract tracing reveals prominent crosstalk between gut non-vagal sensory afferents and adipose sympathetic outflow. Hence, these findings demonstrate a novel gut sensory ghrelin signaling pathway critical for maintaining energy homeostasis.

16.
Anal Chem ; 95(50): 18557-18563, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38050376

RESUMO

Lipids are important biomarkers within the field of disease diagnostics and can serve as indicators of disease progression and predictors of treatment effectiveness. Although lipids can provide important insight into how diseases initiate and progress, mass spectrometric methods for lipid characterization and profiling are limited due to lipid structural diversity, particularly the presence of various lipid isomers. Moreover, the difficulty of handling small-volume samples exacerbates the intricacies of biological analyses. In this work, we have developed a strategy that electromigrates a thin film of a small-volume biological sample directly to the air-liquid interface formed at the tip of a theta capillary. Importantly, we seamlessly integrated in situ biological lipid extraction with accelerated chemical derivatization, enabled by the air-liquid interface, and conducted isomeric structural characterization within a unified platform utilizing theta capillary nanoelectrospray ionization mass spectrometry, all tailored for small-volume sample analysis. We applied this unified platform to the analysis of lipids from small-volume human plasma and Alzheimer's disease mouse serum samples. Accelerated electro-epoxidation of unsaturated lipids at the interface allowed us to characterize lipid double-bond positional isomers. The unique application of electromigration of a thin film to the air-liquid interface in combination with accelerated interfacial reactions holds great potential in small-volume sample analysis for disease diagnosis and prevention.


Assuntos
Lipídeos , Espectrometria de Massas por Ionização por Electrospray , Camundongos , Humanos , Animais , Espectrometria de Massas , Isomerismo , Lipídeos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos
17.
Bioeng Transl Med ; 8(6): e10582, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38023704

RESUMO

Since every biological system requires capillaries to support its oxygenation, design of engineered preclinical models of such systems, for example, vascularized microphysiological systems (vMPS) have gained attention enhancing the physiological relevance of human biology and therapies. But the physiology and function of formed vessels in the vMPS is currently assessed by non-standardized, user-dependent, and simple morphological metrics that poorly relate to the fundamental function of oxygenation of organs. Here, a chained neural network is engineered and trained using morphological metrics derived from a diverse set of vMPS representing random combinations of factors that influence the vascular network architecture of a tissue. This machine-learned algorithm outputs a singular measure, termed as vascular network quality index (VNQI). Cross-correlation of morphological metrics and VNQI against measured oxygen levels within vMPS revealed that VNQI correlated the most with oxygen measurements. VNQI is sensitive to the determinants of vascular networks and it consistently correlates better to the measured oxygen than morphological metrics alone. Finally, the VNQI is positively associated with the functional outcomes of cell transplantation therapies, shown in the vascularized islet-chip challenged with hypoxia. Therefore, adoption of this tool will amplify the predictions and enable standardization of organ-chips, transplant models, and other cell biosystems.

18.
PeerJ ; 11: e16301, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37953778

RESUMO

Background: Chronic kidney disease (CKD) is a significant global health issue characterized by progressive loss of kidney function. Renal interstitial fibrosis (TIF) is a common feature of CKD, but current treatments are seldom effective in reversing TIF. Nicotinamide N-methyltransferase (NNMT) has been found to increase in kidneys with TIF, but its role in renal fibrosis is unclear. Methods: Using mice with unilateral ureteral obstruction (UUO) and cultured renal interstitial fibroblast cells (NRK-49F) stimulated with transforming growth factor-ß1 (TGF-ß1), we investigated the function of NNMT in vivo and in vitro. Results: We performed single-cell transcriptome sequencing (scRNA-seq) on the kidneys of mice and found that NNMT increased mainly in fibroblasts of UUO mice compared to sham mice. Additionally, NNMT was positively correlated with the expression of renal fibrosis-related genes after UUO injury. Knocking down NNMT expression reduced fibroblast activation and was accompanied by an increase in DNA methylation of p53 and a decrease in its phosphorylation. Conclusions: Our findings suggest that chronic kidney injury leads to an accumulation of NNMT, which might decrease p53 methylation, and increase the expression and activity of p53. We propose that NNMT promotes fibroblast activation and renal fibrosis, making NNMT a novel target for preventing and treating renal fibrosis.


Assuntos
Nicotinamida N-Metiltransferase , Insuficiência Renal Crônica , Obstrução Ureteral , Fibrose , Rim/metabolismo , Nicotinamida N-Metiltransferase/genética , Insuficiência Renal Crônica/genética , Proteína Supressora de Tumor p53/metabolismo , Obstrução Ureteral/genética , Animais , Camundongos
19.
Nature ; 623(7987): 580-587, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37938769

RESUMO

Microsatellite repeat expansions within genes contribute to a number of neurological diseases1,2. The accumulation of toxic proteins and RNA molecules with repetitive sequences, and/or sequestration of RNA-binding proteins by RNA molecules containing expanded repeats are thought to be important contributors to disease aetiology3-9. Here we reveal that the adenosine in CAG repeat RNA can be methylated to N1-methyladenosine (m1A) by TRMT61A, and that m1A can be demethylated by ALKBH3. We also observed that the m1A/adenosine ratio in CAG repeat RNA increases with repeat length, which is attributed to diminished expression of ALKBH3 elicited by the repeat RNA. Additionally, TDP-43 binds directly and strongly with m1A in RNA, which stimulates the cytoplasmic mis-localization and formation of gel-like aggregates of TDP-43, resembling the observations made for the protein in neurological diseases. Moreover, m1A in CAG repeat RNA contributes to CAG repeat expansion-induced neurodegeneration in Caenorhabditis elegans and Drosophila. In sum, our study offers a new paradigm of the mechanism through which nucleotide repeat expansion contributes to neurological diseases and reveals a novel pathological function of m1A in RNA. These findings may provide an important mechanistic basis for therapeutic intervention in neurodegenerative diseases emanating from CAG repeat expansion.


Assuntos
Adenosina , Caenorhabditis elegans , Proteínas de Ligação a DNA , Drosophila melanogaster , Doenças Neurodegenerativas , RNA , Expansão das Repetições de Trinucleotídeos , Animais , Humanos , Adenosina/análogos & derivados , Adenosina/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Ligação a DNA/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , RNA/química , RNA/genética , RNA/metabolismo , Expansão das Repetições de Trinucleotídeos/genética , Citoplasma/metabolismo , Modelos Animais de Doenças
20.
Front Oncol ; 13: 1211103, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965453

RESUMO

Background: Despite numerous treatments available, clear cell renal cell carcinoma (ccRCC) remains a deadly and invasive cancer. Anoikis-related genes (ARGs) are essential regulators of tumor metastasis and development. However, the potential roles of ARGs in ccRCC remain unclear. Methods: Based on the TCGA-KIRC cohort and GeneCards database, we identified differentially expressed ARGs in ccRCC. Then a 4 ARGs risk model was created by Cox regression and LASSO. The Kaplan-Meier and receiver operating characteristic (ROC) curves were utilized to verify the predictive efficacy of the prognostic signature. Subsequently, the possible molecular mechanism of ARGs was investigated by functional enrichment analysis. To assess the immune infiltration, immune checkpoint genes, and immune function in various risk groups, single sample gene set enrichment (ssGSEA) algorithm was employed. Furthermore, the low-risk and high-risk groups were compared in terms of tumor mutation burden (TMB). Ultimately, we analyzed the protein expression of these four ARGs utilizing the western blot test. Results: Four genes were utilized to create a risk signature that may predict prognosis, enabling the classification of KIRC patients into groups with low or high risk. The reliability of the signature was examined utilizing survival analysis and ROC analysis. According to the multivariate Cox regression result, the risk score was a reliable independent prognostic predictor for KIRC patients. The novel risk model could differentiate between KIRC patients with various clinical outcomes and represent KIRC's specific immune status. An analysis of the correlation of TMB and risk score indicated a positive correlation between them, with high TMB being potentially linked to worse outcomes. Conclusion: Based on our findings, the prognostic signature of ARGs may be employed as an independent prognostic factor for ccRCC patients. It may introduce alternative perspectives on prognosis evaluation and serve as a prominent reference for personalized and precise therapy in KIRC.

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