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Mounting effective immunity against pathogens and tumours relies on the successful metabolic programming of T cells by extracellular fatty acids1-3. Fatty-acid-binding protein 5 (FABP5) has a key role in this process by coordinating the efficient import and trafficking of lipids that fuel mitochondrial respiration to sustain the bioenergetic requirements of protective CD8+ T cells4,5. However, the mechanisms that govern this immunometabolic axis remain unexplored. Here we report that the cytoskeletal organizer transgelin 2 (TAGLN2) is necessary for optimal fatty acid uptake, mitochondrial respiration and anticancer function in CD8+ T cells. TAGLN2 interacts with FABP5 to facilitate its cell surface localization and function in activated CD8+ T cells. Analyses of ovarian cancer specimens revealed that endoplasmic reticulum (ER) stress responses induced by the tumour microenvironment repress TAGLN2 in infiltrating CD8+ T cells, thereby enforcing their dysfunctional state. Restoring TAGLN2 expression in ER-stressed CD8+ T cells increased their lipid uptake, mitochondrial respiration and cytotoxic capacity. Accordingly, chimeric antigen receptor T cells overexpressing TAGLN2 bypassed the detrimental effects of tumour-induced ER stress and demonstrated therapeutic efficacy in mice with metastatic ovarian cancer. Our study establishes the role of cytoskeletal TAGLN2 in T cell lipid metabolism and highlights the potential to enhance cellular immunotherapy in solid malignancies by preserving the TAGLN2-FABP5 axis.
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Blue light, a high-energy radiation in the visible light spectrum, was recently reported to induce skin pigmentation. In this study, we investigated the involvement of TRPV1-mediated signaling along with OPN3 in blue light-induced melanogenesis as well as its signaling pathway. Operating downstream target of OPN3 in blue light-induced melanogenesis, blue light activated TRPV1 and upregulated its expression, resulting in calcium influx. Calcium ion induced the activation of calcium/calmodulin-dependent protein kinase II and MAPK. It also downregulated clusterin expression, leading to the nuclear translocation of PAX3, ultimately affecting melanin synthesis. In addition, blue light interfered with autophagy-mediated regulation of melanosomes by decreasing not only the interaction between clusterin and LC3B but the expression of activating transcription factor family. These findings demonstrate that the pigmenting effects of blue light are mediated by calcium/calmodulin-dependent protein kinase II- and MAPK-mediated signaling as well as clusterin-dependent inhibition of autophagy through OPN3-TRPV1-calcium influx, suggesting, to our knowledge, a previously unreported signaling pathway through which blue light regulates melanocyte biology. Furthermore, these results suggest that TRPV1 and clusterin could be potential therapeutic targets for blue light-induced pigmentation due to prolonged exposure to blue light.
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Iron accumulation in tumors contributes to disease progression and chemoresistance. Although targeting this process can influence various hallmarks of cancer, the immunomodulatory effects of iron chelation in the tumor microenvironment are unknown. Here, we report that treatment with deferiprone, an FDA-approved iron chelator, unleashes innate immune responses that restrain ovarian cancer. Deferiprone reprogrammed ovarian cancer cells toward an immunostimulatory state characterized by the production of type-I IFN and overexpression of molecules that activate NK cells. Mechanistically, these effects were driven by innate sensing of mitochondrial DNA in the cytosol and concomitant activation of nuclear DNA damage responses triggered upon iron chelation. Deferiprone synergized with chemotherapy and prolonged the survival of mice with ovarian cancer by bolstering type-I IFN responses that drove NK cell-dependent control of metastatic disease. Hence, iron chelation may represent an alternative immunotherapeutic strategy for malignancies that are refractory to current T-cell-centric modalities. Significance: This study uncovers that targeting dysregulated iron accumulation in ovarian tumors represents a major therapeutic opportunity. Iron chelation therapy using an FDA-approved agent causes immunogenic stress responses in ovarian cancer cells that delay metastatic disease progression and enhance the effects of first-line chemotherapy. See related commentary by Bell and Zou, p. 1771.
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Imunidade Inata , Quelantes de Ferro , Neoplasias Ovarianas , Feminino , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Humanos , Animais , Quelantes de Ferro/uso terapêutico , Quelantes de Ferro/farmacologia , Camundongos , Imunidade Inata/efeitos dos fármacos , Linhagem Celular Tumoral , Deferiprona/uso terapêutico , Deferiprona/farmacologia , Metástase Neoplásica , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacosRESUMO
Adiponectin, a crucial protein hormone originating from adipose tissue, regulates key metabolic processes, including lipid metabolism, mitochondrial activity, and insulin sensitivity. These pleiotropic roles of adiponectin, along with its inverse correlation with metabolic disorders such as obesity, type II diabetes, and atherosclerosis, establish this protein as a potential therapeutic target. However, due to this complexity, challenges have arisen in its production with a natural conformation in bacterial or mammalian expression systems, hindering clinical translation. Furthermore, while inducers for adiponectin secretion or chemical agonists targeting adiponectin receptors have shown promise in laboratory settings, clinical studies with these agents have not yet been conducted. This study proposes a method for isolating and purifying natural high molecular weight (HMW) adiponectin from discarded plasma fractions during the conventional pharmaceutical protein manufacturing process. The process involved Cohn-Oncley fractionation, initial chromatography using reduced cellufine formyl, and subsequent purification via DEAE Sepharose chromatography. Characterization involved gel electrophoresis and biological assays on a hepatocyte cell-line. The purification process effectively captured adiponectin from the I + III paste, demonstrating that this fraction contained a significant portion of total plasma adiponectin. The two-step chromatography led to highly purified HMW adiponectin, confirmed by native-PAGE showing a 780 kDa multimeric complex. Biological assessments demonstrated normal downstream signaling, with HMW adiponectin inducing AMPK phosphorylation. This study demonstrates the feasibility of obtaining purified HMW adiponectin by repurposing plasma fractionation processes. It offers a promising avenue for the HMW adiponectin production, tapping into HMW adiponectin's therapeutic potential against metabolic disorders while optimizing plasma resource utilization in healthcare.
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Adiponectina , Peso Molecular , Humanos , Adiponectina/sangue , Adiponectina/isolamento & purificação , Adiponectina/química , Adiponectina/metabolismo , Cromatografia por Troca Iônica/métodosRESUMO
Background: We previously demonstrated the validity of a regression model that included ethnicity as a novel predictor for predicting normative brain volumes in old age. The model was optimized using brain volumes measured with a standard tool FreeSurfer. Objective: Here we further verified the prediction model using newly estimated brain volumes from Neuro I, a quantitative brain analysis system developed for Korean populations. Methods: Lobar and subcortical volumes were estimated from MRI images of 1,629 normal Korean and 786 Caucasian subjects (age range 59-89) and were predicted in linear regression from ethnicity, age, sex, intracranial volume, magnetic field strength, and scanner manufacturers. Results: In the regression model predicting the new volumes, ethnicity was again a substantial predictor in most regions. Additionally, the model-based z-scores of regions were calculated for 428 AD patients and the matched controls, and then employed for diagnostic classification. When the AD classifier adopted the z-scores adjusted for ethnicity, the diagnostic accuracy has noticeably improved (AUCâ=â0.85, ΔAUCâ=â+â0.04, Dâ=â4.10, pâ<â0.001). Conclusions: Our results suggest that the prediction model remains robust across different measurement tool, and ethnicity significantly contributes to the establishment of norms for brain volumes and the development of a diagnostic system for neurodegenerative diseases.
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Doença de Alzheimer , Encéfalo , Imageamento por Ressonância Magnética , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Alzheimer/etnologia , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Doença de Alzheimer/diagnóstico , Povo Asiático , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Tamanho do Órgão , População Branca , População do Leste AsiáticoRESUMO
The worldwide appearance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has generated significant concern and posed a considerable challenge to global health. Phosphorylation is a common post-translational modification that affects many vital cellular functions and is closely associated with SARS-CoV-2 infection. Precise identification of phosphorylation sites could provide more in-depth insight into the processes underlying SARS-CoV-2 infection and help alleviate the continuing COVID-19 crisis. Currently, available computational tools for predicting these sites lack accuracy and effectiveness. In this study, we designed an innovative meta-learning model, Meta-Learning for Serine/Threonine Phosphorylation (MeL-STPhos), to precisely identify protein phosphorylation sites. We initially performed a comprehensive assessment of 29 unique sequence-derived features, establishing prediction models for each using 14 renowned machine learning methods, ranging from traditional classifiers to advanced deep learning algorithms. We then selected the most effective model for each feature by integrating the predicted values. Rigorous feature selection strategies were employed to identify the optimal base models and classifier(s) for each cell-specific dataset. To the best of our knowledge, this is the first study to report two cell-specific models and a generic model for phosphorylation site prediction by utilizing an extensive range of sequence-derived features and machine learning algorithms. Extensive cross-validation and independent testing revealed that MeL-STPhos surpasses existing state-of-the-art tools for phosphorylation site prediction. We also developed a publicly accessible platform at https://balalab-skku.org/MeL-STPhos. We believe that MeL-STPhos will serve as a valuable tool for accelerating the discovery of serine/threonine phosphorylation sites and elucidating their role in post-translational regulation.
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COVID-19 , SARS-CoV-2 , Humanos , Fosforilação , SARS-CoV-2/metabolismo , Serina/metabolismo , Treonina/metabolismoRESUMO
Oxidative stress plays an essential role in the development of Parkinson's disease (PD). 8-oxo-7,8-dihydroguanine (8-oxodG, oxidized guanine) is the most abundant oxidative stress-mediated DNA lesion. However, its contributing role in underlying PD pathogenesis remains unknown. In this study, we hypothesized that 8-oxodG can generate novel α-synuclein (α-SYN) mutants with altered pathologic aggregation through a phenomenon called transcriptional mutagenesis (TM). We observed a significantly higher accumulation of 8-oxodG in the midbrain genomic DNA from PD patients compared to age-matched controls, both globally and region specifically to α-SYN. In-silico analysis predicted that forty-three amino acid positions can contribute to TM-derived α-SYN mutation. Here, we report a significantly higher load of TM-derived α-SYN mutants from the midbrain of PD patients compared to controls using a sensitive PCR-based technique. We found a novel Serine42Tyrosine (S42Y) α-SYN as the most frequently detected TM mutant, which incidentally had the highest predicted aggregation score amongst all TM variants. Immunohistochemistry of midbrain sections from PD patients using a newly characterized antibody for S42Y identified S42Y-laden Lewy bodies (LB). We further demonstrated that the S42Y TM variant significantly accelerates WT α-SYN aggregation by cell and recombinant protein-based assays. Cryo-electron tomography revealed that S42Y exhibits considerable conformational heterogeneity compared to WT fibrils. Moreover, S42Y exhibited higher neurotoxicity compared to WT α-SYN as shown in mouse primary cortical cultures and AAV-mediated overexpression in the substantia nigra of C57BL/6 J mice. To our knowledge, this is the first report describing the possible contribution of TM-generated mutations of α-SYN to LB formation and PD pathogenesis.
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Doença de Parkinson , Humanos , Animais , Camundongos , Doença de Parkinson/patologia , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , 8-Hidroxi-2'-Desoxiguanosina , Camundongos Endogâmicos C57BL , Mutagênese , DNARESUMO
Diabetes mellitus has become a major public health concern associated with high mortality and reduced life expectancy and can cause blindness, heart attacks, kidney failure, lower limb amputations, and strokes. A new generation of antidiabetic peptides (ADPs) that act on ß-cells or T-cells to regulate insulin production is being developed to alleviate the effects of diabetes. However, the lack of effective peptide-mining tools has hampered the discovery of these promising drugs. Hence, novel computational tools need to be developed urgently. In this study, we present ADP-Fuse, a novel two-layer prediction framework capable of accurately identifying ADPs or non-ADPs and categorizing them into type 1 and type 2 ADPs. First, we comprehensively evaluated 22 peptide sequence-derived features coupled with eight notable machine learning algorithms. Subsequently, the most suitable feature descriptors and classifiers for both layers were identified. The output of these single-feature models, embedded with multiview information, was trained with an appropriate classifier to provide the final prediction. Comprehensive cross-validation and independent tests substantiate that ADP-Fuse surpasses single-feature models and the feature fusion approach for the prediction of ADPs and their types. In addition, the SHapley Additive exPlanation method was used to elucidate the contributions of individual features to the prediction of ADPs and their types. Finally, a user-friendly web server for ADP-Fuse was developed and made publicly accessible (https://balalab-skku.org/ADP-Fuse), enabling the swift screening and identification of novel ADPs and their types. This framework is expected to contribute significantly to antidiabetic peptide identification.
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Diabetes Mellitus , Hipoglicemiantes , Peptídeos , Sequência de Aminoácidos , Algoritmos , Aprendizado de Máquina , Biologia ComputacionalRESUMO
The challenge of eradicating leukemia in patients with acute myelogenous leukemia (AML) after initial cytoreduction has motivated modern efforts to combine synergistic active modalities including immunotherapy. Recently, the ETCTN/CTEP 10026 study tested the combination of the DNA methyltransferase inhibitor decitabine together with the immune checkpoint inhibitor ipilimumab for AML/myelodysplastic syndrome (MDS) either after allogeneic hematopoietic stem cell transplantation (HSCT) or in the HSCT-naïve setting. Integrative transcriptome-based analysis of 304 961 individual marrow-infiltrating cells for 18 of 48 subjects treated on study revealed the strong association of response with a high baseline ratio of T to AML cells. Clinical responses were predominantly driven by decitabine-induced cytoreduction. Evidence of immune activation was only apparent after ipilimumab exposure, which altered CD4+ T-cell gene expression, in line with ongoing T-cell differentiation and increased frequency of marrow-infiltrating regulatory T cells. For post-HSCT samples, relapse could be attributed to insufficient clearing of malignant clones in progenitor cell populations. In contrast to AML/MDS bone marrow, the transcriptomes of leukemia cutis samples from patients with durable remission after ipilimumab monotherapy showed evidence of increased infiltration with antigen-experienced resident memory T cells and higher expression of CTLA-4 and FOXP3. Altogether, activity of combined decitabine and ipilimumab is impacted by cellular expression states within the microenvironmental niche of leukemic cells. The inadequate elimination of leukemic progenitors mandates urgent development of novel approaches for targeting these cell populations to generate long-lasting responses. This trial was registered at www.clinicaltrials.gov as #NCT02890329.
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Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Humanos , Ipilimumab/uso terapêutico , Decitabina/uso terapêutico , Síndromes Mielodisplásicas/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , RecidivaRESUMO
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has made significant impacts on global public health, including the development of several skin diseases that have arisen primarily as a result of the pandemic. Owing to the widespread expansion of coronavirus disease 19 (COVID-19), the development of effective treatments for these skin diseases is drawing attention as an important social issue. For many centuries, ginseng and its major active ingredients, ginsenosides and saponins, have been widely regarded as herbal medicines. Further, the anti-viral action of ginseng suggests its potential effectiveness as a therapeutic agent against COVID-19. Thus, the aim of this review was to examine the association of skin lesions with COVID-19 and the effect of ginseng as a therapeutic agent to treat skin diseases induced by COVID-19 infection. We classified COVID-19-related skin disorders into three categories: caused by inflammatory, immune, and complex (both inflammatory and immune) responses and evaluated the evidence for ginseng as a treatment for each category. This review offers comprehensive evidence on the improvement of skin disorders induced by SARS-CoV-2 infection using ginseng and its active constituents.
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Mounting effective immunity against pathogens and tumors relies on the successful metabolic programming of T cells by extracellular fatty acids1-3. During this process, fatty-acid-binding protein 5 (FABP5) imports lipids that fuel mitochondrial respiration and sustain the bioenergetic requirements of protective CD8+ T cells4,5. Importantly, however, the mechanisms governing this crucial immunometabolic axis remain unexplored. Here we report that the cytoskeletal organizer Transgelin 2 (TAGLN2) is necessary for optimal CD8+ T cell fatty acid uptake, mitochondrial respiration, and anti-cancer function. We found that TAGLN2 interacts with FABP5, enabling the surface localization of this lipid importer on activated CD8+ T cells. Analysis of ovarian cancer specimens revealed that endoplasmic reticulum (ER) stress responses elicited by the tumor microenvironment repress TAGLN2 in infiltrating CD8+ T cells, enforcing their dysfunctional state. Restoring TAGLN2 expression in ER-stressed CD8+ T cells bolstered their lipid uptake, mitochondrial respiration, and cytotoxic capacity. Accordingly, chimeric antigen receptor T cells overexpressing TAGLN2 bypassed the detrimental effects of tumor-induced ER stress and demonstrated superior therapeutic efficacy in mice with metastatic ovarian cancer. Our study unveils the role of cytoskeletal TAGLN2 in T cell lipid metabolism and highlights the potential to enhance cellular immunotherapy in solid malignancies by preserving the TAGLN2-FABP5 axis.
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Many species in the genus Guettarda are known to exert anti-inflammatory effects and are used as traditional medicinal plants to treat various inflammatory symptoms. However, no studies on the inflammatory activities of Guettarda crispiflora Vahl have been reported. The aim of the study was to investigate in vitro and in vivo the anti-inflammatory effects of a methanol extract of Guettarda crispiflora Vahl (Gc-ME). To determine the anti-inflammatory activity of Gc-ME, lipopolysaccharide (LPS)-, poly(I:C)-, or Pam3CSK4-treated RAW264.7 cells, HCl/EtOH- and LPS-treated mice were employed for in vitro and in vivo tests. LPS-induced nitric oxide production in RAW264.7 cells was determined by Griess assays and cytokine gene expression in LPS-activated RAW264.7 cells, confirmed by RT- and real-time PCR. Transcriptional activation was evaluated by luciferase reporter gene assay. Target protein validation was assessed by Western blot analysis and cellular thermal shift assays (CETSA) with LPS-treated RAW264.7 and gene-transfected HEK293 cells. Using both a HCl/EtOH-induced gastritis model and an LPS-induced lung injury model, inflammatory states were checked by scoring or evaluating gastric lesions, lung edema, and lung histology. Phytochemical fingerprinting of Gc-ME was observed by using liquid chromatography-mass spectrometry. Nitric oxide production induced by LPS and Pam3CSK4 in RAW264.7 cells was revealed to be reduced by Gc-ME. The LPS-induced upregulation of iNOS, COX-2, IL-6, and IL-1ß was also suppressed by Gc-ME treatment. Gc-ME downregulated the promotor activities of AP-1 and NF-κB triggered by MyD88- and TRIF induction. Upstream signaling proteins for NF-κB activation, namely, p-p50, p-p65, p-IκBα, and p-Src were all downregulated by Ch-EE. Moreover, Src was revealed to be directly targeted by Gc-ME. This extract, orally treated strongly, attenuated the inflammatory symptoms in HCl/EtOH-treated stomachs and LPS-treated lungs. Therefore, these results strongly imply that Guettarda crispiflora can be developed as a promising anti-inflammatory remedy with Src-suppressive properties.
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Ultraviolet (UV) irradiation induces ROS production, which activates activator protein (AP)-1 and nuclear factor (NF)-κB signaling and downstream molecules, ultimately triggering the generation of matrix metalloproteinases (MMPs) and degradation of collagen. The aim of this study was to investigate the protective effect of methanol extract from Malus baccata (L.) Borkh (Mb-ME) against aging. DPPH and ABTS assays showed that Mb-ME had a significant antioxidant capacity. Flow cytometry results indicated that Mb-ME attenuated UVB and H2O2-stimulated apoptosis and reactive oxygen species (ROS) generation. RT-PCR analysis in HaCaT and HDF cells suggested that Mb-ME treatment blocked the expression of MMPs, COX-2, IL-1ß, IL-6, HYALs, and p53 while promoting the levels of TGM1, FLG, HASs, Sirt1, and Col1A1. Mechanically, Mb-ME inhibited the phosphorylation of MAP kinases and NF-κB signaling. Overall, these results strongly suggest that Mb-ME can be developed as an antiaging therapy.
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Obesity is associated with increased cancer risk and weak responses to vaccination and sepsis treatment. Although dendritic cells (DCs) are fundamental for the initiation and maintenance of competent immune responses against pathogens and tumors, how obesity alters the normal physiology of these myeloid cells remains largely unexplored. In this study, we report that obesity caused by prolonged high-fat diet feeding disrupts the metabolic and functional status of mouse splenic DCs (SpDCs). High-fat diet-induced obesity drastically altered the global transcriptional profile of SpDCs, causing severe changes in the expression of gene programs implicated in lipid metabolism and mitochondrial function. SpDCs isolated from obese mice demonstrated enhanced mitochondrial respiration provoked by increased fatty acid oxidation (FAO), which drove the intracellular accumulation of reactive oxygen species that impaired Ag presentation to T cells. Accordingly, treatment with the FAO inhibitor etomoxir, or antioxidants such as vitamin E or N-acetyl-l-cysteine, restored the Ag-presenting capacity of SpDCs isolated from obese mice. Our findings reveal a major detrimental effect of obesity in DC physiology and suggest that controlling mitochondrial FAO or reactive oxygen species overproduction may help improve DC function in obese individuals.
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Dieta Hiperlipídica , Ácidos Graxos , Animais , Células Dendríticas , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos/metabolismo , Homeostase , Metabolismo dos Lipídeos , Camundongos , Camundongos Obesos , Mitocôndrias/metabolismo , Obesidade/metabolismo , Oxirredução , Espécies Reativas de Oxigênio/metabolismoRESUMO
Lysophosphatidic acid (LPA) is a bioactive lipid enriched in the tumor microenvironment of immunosuppressive malignancies such as ovarian cancer. Although LPA enhances the tumorigenic attributes of cancer cells, the immunomodulatory activity of this phospholipid messenger remains largely unexplored. Here, we report that LPA operates as a negative regulator of type I interferon (IFN) responses in ovarian cancer. Ablation of the LPA-generating enzyme autotaxin (ATX) in ovarian cancer cells reprogrammed the tumor immune microenvironment, extended host survival, and improved the effects of therapies that elicit protective responses driven by type I IFN. Mechanistically, LPA sensing by dendritic cells triggered PGE2 biosynthesis that suppressed type I IFN signaling via autocrine EP4 engagement. Moreover, we identified an LPA-controlled, immune-derived gene signature associated with poor responses to combined PARP inhibition and PD-1 blockade in patients with ovarian cancer. Controlling LPA production or sensing in tumors may therefore be useful to improve cancer immunotherapies that rely on robust induction of type I IFN. SIGNIFICANCE: This study uncovers that ATX-LPA is a central immunosuppressive pathway in the ovarian tumor microenvironment. Ablating this axis sensitizes ovarian cancer hosts to various immunotherapies by unleashing protective type I IFN responses. Understanding the immunoregulatory programs induced by LPA could lead to new biomarkers predicting resistance to immunotherapy in patients with cancer. See related commentary by Conejo-Garcia and Curiel, p. 1841. This article is highlighted in the In This Issue feature, p. 1825.
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Interferon Tipo I , Lisofosfolipídeos , Neoplasias Ovarianas , Feminino , Humanos , Lisofosfolipídeos/genética , Lisofosfolipídeos/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Receptores de Ácidos Lisofosfatídicos/genética , Receptores de Ácidos Lisofosfatídicos/metabolismo , Microambiente TumoralRESUMO
While harmful effects of blue light on skin cells have been recently reported, there are few studies regarding natural products that alleviate its negative effects. Therefore, we investigated ameliorating effects of yellow chaste weed (YCW) (Helichrysum arenarium) extract and its components, apigenin and galangin, on blue light-irradiated HaCaT cells. In this study, we found that YCW extract improved the reduced proliferation of HaCaT cells induced by blue light-irradiation and reduced blue light-induced production of reactive oxygen species (ROS) levels. We also found that apigenin and galangin, the main components of YCW extract, showed the same activities as YCW extract. In experiments examining molecular mechanisms of YCW extract and its components such as apigenin and galangin, they all reduced expression of transient receptor potential vanilloid member 1 (TRPV1), its phosphorylation, and calcium ion (Ca2+) influx induced by blue light irradiation. In addition, apigenin and galangin regulated phosphorylation of mitogen-activated protein kinases (MAPKs). They also reduced phosphorylation of mammalian sterile 20-like kinase-1/2 (MST-1/2), inducing phosphorylation of Akt (protein kinase B), one downstream molecule of MST-1/2. Moreover, apigenin and galangin promoted translocation of Forkhead box O3 (FoxO3a) from the nucleus to the cytosol by phosphorylating FoxO3a. Besides, apigenin and galangin interrupted blue light influences on expression of nuclear and secretory clusterin. Namely, they attenuated both upregulation of nuclear clusterin and downregulation of secretory clusterin induced by blue light irradiation. We also found that they downregulated apoptotic protein Bcl-2 associated X protein (Bax) and conversely upregulated anti-apoptotic protein B-cell lymphoma 2 (Bcl-2). Collectively, these findings indicate that YCW extract and its components, apigenin and galangin, antagonize the blue light-induced damage to the keratinocytes by regulating TRPV1/clusterin/FoxO3a and MAPK signaling.
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Apigenina , Células HaCaT , Animais , Apigenina/farmacologia , Proliferação de Células , Flavonoides , Humanos , Mamíferos , Estresse OxidativoRESUMO
Potential biomarkers for Alzheimer's disease (AD) include amyloid ß1-42 (Aß1-42), t-Tau, p-Tau181, neurofilament light chain (NFL), and neuroimaging biomarkers. Their combined use is useful for diagnosing and monitoring the progress of AD. Therefore, further development of a combination of these biomarkers is essential. We investigated whether plasma NFL/Aß1-42 can serve as a plasma-based primary screening biomarker reflecting brain neurodegeneration and amyloid pathology in AD for monitoring disease progression and early diagnosis. We measured the NFL and Aß1-42 concentrations in the CSF and plasma samples and performed correlation analysis to evaluate the utility of these biomarkers in the early diagnosis and monitoring of AD spectrum disease progression. Pearson's correlation analysis was used to analyse the associations between the fluid biomarkers and neuroimaging data. The study included 136 participants, classified into five groups: 28 cognitively normal individuals, 23 patients with preclinical AD, 22 amyloid-negative patients with amnestic mild cognitive impairment, 32 patients with prodromal AD, and 31 patients with AD dementia. With disease progression, the NFL concentrations increased and Aß1-42 concentrations decreased. The plasma and CSF NFL/Aß1-42 were strongly correlated (r = 0.558). Plasma NFL/Aß1-42 was strongly correlated with hippocampal volume/intracranial volume (r = 0.409). In early AD, plasma NFL/Aß1-42 was associated with higher diagnostic accuracy than the individual biomarkers. Moreover, in preclinical AD, plasma NFL/Aß1-42 changed more rapidly than the CSF t-Tau or p-Tau181 concentrations. Our findings highlight the utility of plasma NFL/Aß1-42 as a non-invasive plasma-based biomarker for early diagnosis and monitoring of AD spectrum disease progression.
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Prasiola japonica is an edible alga, and the ethanol extract of P. japonica (Pj-EE) possesses various biological activities. Interestingly, in a recent study, we observed the potent anti-inflammatory activity of the chloroform fraction of Pj-EE (Pj-EE-CF). Thus, to extend the application of Pj-EE-CF, we further studied its effects on lung injury. To establish an experimental model of lung injury, we nasally administered urban particulate matter UPM 1648a (50 mg/kg) to mice. In addition, BEAS-2B cells were treated with 300 µg/mL of UPM 1648a for in vitro analysis. Intranasal administration of UPM 1648a increased lung injury score, macrophage infiltration, and upregulation of the inflammatory enzyme inducible nitric oxide synthase (iNOS) in lung tissues. On the other hand, oral administration of Pj-EE-CF (25, 50, and 100 mg/kg) alleviated these pathological features as assessed by lung wet/dry ratio, lung injury score, bronchoalveolar lavage fluid (BALF) protein amount in the lung tissues up to 70%, 95%, and 99%, respectively. In addition, Pj-EE-CF down-regulated the release of inflammatory cytokines, interleukins (ILs), tumor necrosis factor (TNF)-α, and interferon (IFN)-γ elevated by UPM 1648a in the lung tissues and lung BALF up to 95%. According to Western blot and luciferase assay, Pj-EE-CF (100 mg/kg in vivo or 50 and 100 µg/mL in vitro) significantly reduced the nuclear factor-κB (NF-κB) signal activated by UPM 1648a. Finally, UPM 1648a increased cellular reactive oxygen species (ROS) levels in BEAS-2B cells, while Pj-EE-CF reduced them. These results suggest that Pj-EE-CF alleviates UPM 1648a-induced lung damage via anti-inflammatory and antioxidant activities and by suppressing NF-κB signaling. In conclusion, these observations imply that Pj-EE-CF could be a practical component of food supplements to mitigate air pollution-derived lung damage.
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Olfactory receptors (ORs), which belong to the G-protein-coupled receptor family, have been widely studied as ectopically expressed receptors in various human tissues, including the skin. However, the physiological functions of only a few OR types have been elucidated in skin cells. All-trans retinoic acid (ATRA) is a well-known medication for various skin diseases. However, many studies have shown that ATRA can have adverse effects, resulting from the suppression of cell proliferation. Here, we investigated the involvement of OR7A17 in the ATRA-induced suppression of human keratinocyte (HaCaT) proliferation. We demonstrated that OR7A17 is expressed in HaCaT keratinocytes, and its expression was downregulated by ATRA. The ATRA-induced downregulation of OR7A17 was attenuated via RAR α or RAR γ antagonist treatment, indicating that the effects of ATRA on OR7A17 expression were mediated through nuclear retinoic acid receptor signaling. Moreover, we found that the overexpression of OR7A17 induced the proliferation of HaCaT cells while counteracting the antiproliferative effect of ATRA. Mechanistically, OR7A17 overexpression reversed the ATRA-induced attenuation of Ca2+ entry. Our findings indicated that ATRA suppresses cell proliferation through the downregulation of OR7A17 via RAR α- and γ-mediated retinoid signaling. Taken together, OR7A17 is a potential therapeutic target for ameliorating the anti-proliferative effects of ATRA.
Assuntos
Proliferação de Células/efeitos dos fármacos , Expressão Gênica , Queratinócitos/efeitos dos fármacos , Receptores Odorantes/genética , Tretinoína/farmacologia , Antineoplásicos/farmacologia , Western Blotting , Cálcio/metabolismo , Linhagem Celular , Proliferação de Células/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Receptores Odorantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Brain aging is becoming an increasingly important topic, and the norms of brain structures are essential for diagnosing neurodegenerative diseases. However, previous studies of the aging brain have mostly focused on Caucasians, not East Asians. The aim of this paper was to examine ethnic differences in the aging process of brain structures or to determine to what extent ethnicity affects the normative values of lobar and subcortical volumes in clinically normal elderly and the diagnosis in multi-racial patients with Alzheimer's disease (AD). Lobar and subcortical volumes were measured using FreeSurfer from MRI data of 1,686 normal Koreans (age range 59-89) and 851 Caucasian, non-Hispanic subjects in the ADNI and OASIS datasets. The regression models were designed to predict brain volumes, including ethnicity, age, sex, intracranial volume (ICV), magnetic field strength (MFS), and MRI scanner manufacturers as independent variables. Ethnicity had a significant effect for all lobar (|ß| > 0.20, p < 0.001) and subcortical regions (|ß| > 0.08, p < 0.001) except left pallidus and bilateral ventricles. To demonstrate the validity of the z-score for AD diagnosis, 420 patients and 420 normal controls were selected evenly from the Korean and Caucasian datasets. The four validation groups divided by race and diagnosis were matched on age and sex using a propensity score matching. We analyzed whether and to what extent the ethnicity adjustment improved the diagnostic power of the logistic regression model that was built using the only z-scores of six regions: bilateral temporal cortices, hippocampi, and amygdalae. The performance of the classifier after ethnicity adjustment was significantly improved compared with the classifier before ethnicity adjustment (ΔAUC = 0.10, D = 7.80, p < 0.001; AUC comparison test using bootstrap). Korean AD dementia patients may not be classified by Caucasian norms of brain volumes because the brain regions vulnerable to AD dementia are bigger in normal Korean elderly peoples. Therefore, ethnicity is an essential factor in establishing normative data for regional volumes in brain aging and applying it to the diagnosis of neurodegenerative diseases.