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Acute lung injury (ALI) caused by sepsis is a common respiratory critical illness with high morbidity and mortality. Protein kinase C-alpha (PRKCA) plays a protective role in sepsis-induced ALI. However, the detailed molecular mechanism of PRKCA in ALI caused by sepsis is unclear. Animal and cell models of sepsis were established by cecal ligation and puncture (CLP)-surgery and lipopolysaccharide (LPS)/interferon-gamma (IFN-γ) treatment, respectively. Lentivirus transfection was used to overexpress PRKCA. H&E staining and lung injury in CLP-surgery mice were evaluated. Gene expression was evaluated using qPCR and Western blotting. The expression of TNF-α, IL-1ß, and IL-6 was examined using qPCR and ELISA. The expression of LC3 and TOM20 was evaluated using immunofluorescence assays. Cell apoptosis was assessed using a flow cytometry assay. The bond between miR-15a-5p and PDK4 was confirmed by dual-luciferase reporter gene and RNA immunoprecipitation assays. In vivo and in vitro, PRKCA overexpression reduced lung injury to prompt mitophagy and inhibit the inflammatory response, ROS production, and cell apoptosis. miR-15a-5p was highly expressed in macrophages treated with LPS/IFN-γ and was negatively mediated by PRKCA. The overexpression of miR-15a-5p reduced the effects of PRKCA upregulation in macrophages. miR-15a-5p could restrain mitophagy in LPS/IFN-γ-treated macrophages by directly targeting PDK4. Furthermore, PDK4 knockdown reversed the inhibition of cell apoptosis and inflammatory factor release caused by miR-15a-5p silencing. The PRKCA/miR-15a-5p/PDK4 axis alleviated ALI caused by sepsis by promoting mitophagy and repressing anti-inflammatory response.
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Lesión Pulmonar Aguda , MicroARNs , ARN Largo no Codificante , Sepsis , Animales , Ratones , Lesión Pulmonar Aguda/etiología , Apoptosis/genética , Lipopolisacáridos , MicroARNs/genética , MicroARNs/metabolismo , Mitofagia , Proteína Quinasa C-alfa , Sepsis/complicaciones , Sepsis/genéticaRESUMEN
Background: Nephrotoxicity, especially acute kidney injury (AKI), is the main dose-limiting toxicity of cisplatin. Although recent studies showed that curcumin prevented cisplatin-induced AKI effectively, further studies to understand the mechanism are required.Methods: We established an AKI mouse model. Male C57BL/6 mice were assigned to three groups: saline group (control), cisplatin group (CP), and curcumin + cisplatin group (CP + Cur). The CP group received a single intraperitoneal (i.p.) injection of cisplatin, while the control group received saline. The CP + Cur group received i.p. curcumin three days before cisplatin injection and curcumin administered for another three days until the day before euthanization. Renal injury was assessed by serological and histological analysis. Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) were used to detect the phosphatase and tensin homolog (PTEN), and microRNA (miR)-181a expression in the renal tissues. Bioinformatics prediction and western blotting methods validated the targets of miR-181a in vitro.Results: Curcumin treatment alleviated cisplatin-induced nephrotoxicity as validated by the blood urea nitrogen (BUN) values, and histological analysis of kidneys. At the molecular level, curcumin treatment decreased miR-181a expression level, which was induced by cisplatin and restored the in vivo expression of PTEN, which was suppressed by cisplatin. We verified the direct regulation of PTEN by miR-181a in cultured human embryonic kidney 293T cells.Conclusions: We showed the involvement of miR-181a/PTEN axis in the renoprotective effect of curcumin against cisplatin-induced AKI, and provide new evidence on the ability of curcumin to alleviate cisplatin-induced nephrotoxicity.
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Lesión Renal Aguda/prevención & control , Antiinflamatorios no Esteroideos/farmacología , Curcumina/farmacología , MicroARNs/metabolismo , Fosfohidrolasa PTEN/metabolismo , Lesión Renal Aguda/inducido químicamente , Animales , Apoptosis/efectos de los fármacos , Nitrógeno de la Urea Sanguínea , Cisplatino/toxicidad , Regulación de la Expresión Génica , Riñón/patología , Masculino , Ratones , Ratones Endogámicos C57BLRESUMEN
Due to the cardiotoxicity of doxorubicin (DOX), its clinical application is limited. Lipid peroxidation caused by excessive ferrous iron is believed to be a key molecular mechanism of DOX-induced cardiomyopathy (DIC). Dexrazoxane (DXZ), an iron chelator, is the only drug approved by the FDA for reducing DIC, but it has many side effects and cannot be used as a preventive drug in clinical practice. Single-nucleus RNA sequencing (snRNA-seq) analysis identified myocardial and epithelial cells that are susceptible to DOX-induced ferroptosis. The glutathione peroxidase 4 (GPX4) activator selenomethione (SeMet) significantly reduced polyunsaturated fatty acids (PUFAs) and oxidized lipid levels in vitro. Consistently, SeMet significantly decreased DOX-induced lipid peroxidation in H9C2 cells and mortality in C57BL/6 mice compared to DXZ, ferrostatin-1, and normal saline. SeMet can effectively reduce serum markers of cardiac injury in C57BL/6 mice and breast cancer patients. Depletion of the GPX4 gene in C57BL/6 mice resulted in an increase in polyunsaturated fatty acid (PUFA) levels and eliminated the protective effect of SeMet against DIC. Notably, SeMet exerted antitumor effects on breast cancer models with DOX while providing cardiac protection for the same animal without detectable toxicities. These findings suggest that pharmacological activation of GPX4 is a valuable and promising strategy for preventing the cardiotoxicity of doxorubicin.
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Neoplasias de la Mama , Cardiomiopatías , Humanos , Ratones , Animales , Femenino , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Cardiotoxicidad/etiología , Ratones Endogámicos C57BL , Cardiomiopatías/inducido químicamente , Cardiomiopatías/tratamiento farmacológico , Cardiomiopatías/patología , Doxorrubicina/efectos adversos , Ácidos Grasos InsaturadosRESUMEN
BACKGROUND: Thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA) is a rare nasopharyngeal malignant tumor that is easy to misdiagnose. Immunohistochemistry plays an indispensable role in distinguishing TL-LGNPPA from other malignancies. However, there is no article to summarize the immunohistochemical characteristics of TL-LGNPPA. Herein, we report a case of TL-LGNPPA and present the immunohistochemical results reported in the Chinese literature. METHODS: An electronic search of the CNKI (China National Knowledge Infrastructure) database was performed. From our literature survey, 53 cases of TL-LGNPPA (including the case described in this report) have been identified in China. We summarize the Chinese literature's clinical characteristics, immunohistochemical results, treatments, and prognosis of 53 cases. RESULTS: Based on our literature survey, 53 cases of TL-LGNPPA (including the case described in this report) have been reported in China. We found TL-LGNPPA and papillary thyroid carcinoma were positive for TTF-1 and CK19. TL-LGNPPA was negative for TG and PAX-8, whereas papillary thyroid carcinoma was positive for TG and PAX-8. However, negative expression of TTF-1 and positive expression of TG were also found in some TL-LGNPPA cases. Our literature survey found that all TL-LGNPPA cases were negative for PAX-8.Therefore, we suggest that simultaneous immunohistochemical determination of TTF-1 and CK19, as well as TG and PAX-8, can increase the diagnostic accuracy of TL-LGNPPA. CONCLUSION: The 4th edition of the World Health Organization Classification of Head and Neck Tumors (WHO-HNT) indicates that NPPA with positive expression of cytokeratin 19 (CK19) and TTF-1 and negative expression of TG is called TL-LGNPPA.
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Adenocarcinoma Papilar , Neoplasias Nasofaríngeas , Neoplasias de la Tiroides , Humanos , Cáncer Papilar Tiroideo , Adenocarcinoma Papilar/patología , Neoplasias Nasofaríngeas/patología , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/patología , Biomarcadores de TumorRESUMEN
OBJECTIVE: Rheumatoid arthritis (RA) is considered to be a chronic immune disease pathologically characterized by synovial inflammation and bone destruction. At present, the potential pathogenesis of RA is still unclear. Hub genes are recognized to play a pivotal role in the occurrence and progression of RA. METHODS: Firstly, we attempted to screen hub genes that are associated with RA, to clarify the underlying pathological mechanisms of RA, and to offer potential treatment methods for RA. We acquired these datasets (GSE12021, GSE55235, and GSE55457) of RA patients and healthy samples from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were recognized via R software. Then, Gene ontology (GO) functional analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were utilized to deeply explore the underlying biological functions and pathways closely associated with RA. In addition, a protein-protein interaction (PPI) network was built to further evaluate and screen for hub genes. Finally, on the basis of the results of PPI analysis, we confirmed the mRNA expression levels of five hub genes in the synovial tissue of rats modeled with RA. RESULTS: In the human microarray datasets, LCK, JAK2, SOCS3, STAT1, and EGFR were identified as hub genes associated with RA by bioinformatics analysis. Furthermore, we verified the differential expression levels of hub genes in rat synovial tissues via qRT-PCR (P < 0.05). CONCLUSIONS: Our findings suggest that the hub genes LCK, JAK2, SOCS3, STAT1, and EGFR might have vital roles in the progression of RA and may offer novel therapeutic treatments for RA.
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Background: Rheumatoid arthritis (RA) is recognized as a chronic inflammatory disease featured by pathological synovial inflammation. Currently, the underlying pathophysiological mechanisms of RA remain unclear. In the study, we attempted to explore the underlying mechanisms of RA and provide potential targets for the therapy of RA via bioinformatics analysis. Methods: We downloaded four microarray datasets (GSE77298, GSE55235, GSE12021, and GSE55457) from the GEO database. Firstly, GSE77298 and GSE55457 were identified DEGs by the "limma" and "sva" packages of R software. Then, we performed GO, KEGG, and GSEA enrichment analyses to further analyze the function of DEGs. Hub genes were screened using LASSO analysis and SVM-RFE analysis. To further explore the differences of the expression of hub genes in healthy control and RA patient synovial tissues, we calculated the ROC curves and AUC. The expression levels of hub genes were verified in synovial tissues of normal and RA rats by qRT-PCR and western blot. Furthermore, the CIBERSORTx was implemented to assess the differences of infiltration in 22 immune cells between normal and RA synovial tissues. We explored the association between hub genes and infiltrating immune cells. Results: CRTAM, CXCL13, and LRRC15 were identified as RA's potential hub genes by machine learning and LASSO algorithms. In addition, we verified the expression levels of three hub genes in the synovial tissue of normal and RA rats by PCR and western blot. Moreover, immune cell infiltration analysis showed that plasma cells, T follicular helper cells, M0 macrophages, M1 macrophages, and gamma delta T cells may be engaged in the development and progression of RA. Conclusions: In brief, our study identified and validated that three hub genes CRTAM, CXCL13, and LRRC15 might involve in the pathological development of RA, which could provide novel perspectives for the diagnosis and treatment with RA.
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Artritis Reumatoide , Redes Reguladoras de Genes , Ratas , Animales , Ontología de Genes , Redes Reguladoras de Genes/genética , Perfilación de la Expresión Génica , Transcriptoma/genética , Artritis Reumatoide/metabolismo , Biología ComputacionalRESUMEN
OBJECTIVE: The clinical symptoms of rheumatoid arthritis (RA) have significant circadian rhythms, with morning stiffness and joint pain. Moxibustion is effective in the treatment of RA, while the underlying therapeutic mechanisms remain limited. Thus, we explored whether moxibustion could adjust the circadian rhythm of RA by modulating the core clock genes CLOCK and BMAL1 at the molecular level. METHODS: 144 Sprague Dawley rats were randomly divided into four groups: control group (group A), model group (group B), 7-9 am moxibustion treatment group (group C), and 5-7 pm moxibustion treatment group (group D). Each group was divided into 6 time points (0 am, 4 am, 8 am, 12 N, 6 pm, and 8 pm) with an equal number of rats at each time point. Except for group A, all rats were injected with Freund's Complete Adjuvant (FCA) 0.15 ml on the right foot pad to establish the RA model. The rats of the two moxibustion treatment groups were respectively subjected to moxibustion at 7-9 am and 5-7 pm. After 3 weeks of treatment, the tissues were collected at 6 time points during the next 24 hours. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to test the mRNA expression of CLOCK and BMAL1 in the hypothalamus and synovial tissues. CLOCK and BMAL1 protein expression in synovial tissues were detected with western blot. RESULTS: Compared to group A, group B showed significantly down-regulated expression levels of CLOCK and BMLA1 at synovial tissue (P < 0.05), while no statistically significant difference was found in the hypothalamus (P > 0.05). The expression levels of CLOCK and BMLA1 were up-regulated in the moxibustion treatment groups in different tissues, especially in synovial tissue (P < 0.05) compared to group B. Nevertheless, no difference was observed between groups C and D (P > 0.05). CONCLUSIONS: Moxibustion could treat RA by modulating clock core genes CLOCK and BMAL1 to regulate the circadian rhythm. However, there was no significant difference between the 7-9 am moxibustion treatment group and the 5-7 pm moxibustion treatment group. This study provides a basis for research on moxibustion in the treatment of RA.
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A new flavonoid angelioue (1) together with five known compounds cuminatanol (2), myricetin (3), epigallocatechin (4), taxifolin (5) and dihydromyricetin (6) was isolated from the callus extract of Ampelopsis grossedentata (Hand.-Mazz.) W. T. Wang and the structures were elucidated based on their detailed spectroscopic data. Among the compounds, the new compound angelioue (1) displayed significant antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) with the MIC value of 6.68 µg mL-1 and MBC value of 53.42 µg mL-1; in contrast the other compounds showed moderate to no antibacterial activity. In addition, known dihydromyricetin (6) exhibited potent cytotoxic activities against mouse breast cancer cells (4T1), human lung adenocarcinoma (A549) and human non-small cell lung cancer (NCI-H1975) tumor cell lines with GI50 values of 17.47, 18.91 and 20.50 µM mL-1, respectively. The compounds 1-5 exhibited low micro-molar inhibitory activities. Moreover, the structure-activity relationships of the most active compounds for antibacterial and cytotoxic activities are discussed. The present findings clearly suggest that the A. grossedentata callus is a good source of bioactive compounds.
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Ovarian cancer is a highly lethal malignancy in the female reproductive system. Platinum drugs, represented by cisplatin, are the first-line chemotherapeutic agents for treatment of various malignancies including ovarian cancer, but drug resistance leads to chemotherapy failure. MicroRNAs emerged as promising molecules in reversal of cisplatin resistance. MiR-186 was reported to be downregulated in the cisplatin-resistant ovarian cell lines and miR-186 expression increased cisplatin sensitivity. However, we found the bidirectional regulatory effects of miR-186 on cisplatin sensitivity for the first time that overexpression of miR-186 at low concentration increased the cisplatin sensitivity of ovarian cancer cells A2780/DDP, while high concentration of miR-186 decreased the cisplatin sensitivity. The survival assay in other types of cancer cell lines verified the bidirectional regulatory function of miR-186 on cisplatin sensitivity in dose and cell type dependent manners. MiR-186 suppressed the protein levels of PTEN and PIK3R3 dose-dependently, which are opposite regulatory molecules of the oncogenic AKT pathway. MiR-186 also enhanced the protein levels of apoptotic gene APAF1 dose-dependently. We proposed the final effects of PTEN and APAF1 outweighed PIK3R3 when miR-186 at low concentration so as to increase the cisplatin sensitivity of ovarian cancer cells, while the final effects of PIK3R3 outweighed PTEN and APAF1 when miR-186 at high concentration so as to decrease the cisplatin sensitivity. We concluded the outcome of regulation of these opposite functional molecules contributed to the bidirectional regulatory effects of miR-186 in ovarian cancer cisplatin sensitivity. It deserves more attentions when developing therapeutic strategies based on the bidirectional functional miRNAs.
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Transient receptor potential melastatin 2 (TRPM2) is an important ion channel that represents a potential target for treating injury caused by cerebral ischemia. However, it is unclear whether reducing TRPM2 expression can help repair cerebral injury, and if so what the mechanism underlying this process involves. This study investigated the protective effect of reducing TRPM2 expression on pheochromocytoma (PC12) cells injured by oxygen-glucose deprivation (OGD). PC12 cells were transfected with plasmid encoding TRPM2 shRNAS, then subjected to OGD by incubation in glucose-free medium under hypoxic conditions for 8 hours, after which the cells were allowed to reoxygenate for 24 hours. Apoptotic cells, mitochondrial membrane potentials, reactive oxygen species levels, and cellular calcium levels were detected using flow cytometry. The relative expression of C-X-C motif chemokine ligand 2 (CXCL2), NACHT, LRR, and PYD domain-containing protein 3 (NALP3), and caspase-1 were detected using fluorescence-based quantitative reverse transcription-polymerase chain reaction and western blotting. The rates of apoptosis, mitochondrial membrane potentials, reactive oxygen species levels, and cellular calcium levels in the TRPM2-shRNA + OGD group were lower than those observed in the OGD group. Taken together, these results suggest that TRPM2 knockdown reduces OGD-induced neuronal injury, potentially by inhibiting apoptosis and reducing oxidative stress levels, mitochondrial membrane potentials, intracellular calcium concentrations, and NLRP3 inflammasome activation.
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BACKGROUND: Noninvasive prenatal testing (NIPT) is one of the most commonly employed clinical measures for screening of fetal aneuploidy. Fetal Fraction (ff) has been demonstrated to be one of the key factors affecting the performance of NIPT. Accurate quantification of ff plays vital role in NIPT. METHODS: In this study, we present a new approach, the accurate Quantification of Fetal Fraction with Shallow-Coverage sequencing of maternal plasma DNA (FF-QuantSC), for the estimation of ff in NIPT. The method employs neural network model and utilizes differential genomic patterns between fetal and maternal genomes to quantify ff. RESULTS: Our results show that the predicted ff by FF-QuantSC exhibit high correlation with the Y chromosome-based method on male pregnancies, and achieves the highest accuracy compared with other ff estimation approaches. We also demonstrate that the model generates statistically similar results on both male and female pregnancies. CONCLUSION: FF-QuantSC achieves high accuracy in ff quantification. The method is suitable for application in both male and female pregnancies. Since the method does not require additional information upon NIPT routines, it can be easily incorporated into current NIPT settings without causing extra costs. We believe that FF-QuantSC shall provide valuable additions to NIPT.
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Redes Neurales de la Computación , Pruebas Prenatales no Invasivas/métodos , Análisis de Secuencia de ADN/métodos , Adulto , Femenino , Humanos , Pruebas Prenatales no Invasivas/normas , Embarazo , Sensibilidad y Especificidad , Análisis de Secuencia de ADN/normas , Programas InformáticosRESUMEN
OBJECTIVE: To test different methods for extracting volatile oil from bergamot. METHODS: The determination of bergapten was carried out by RP-HPLC. Four different ways of organic solvent extraction, steam-input distillation, distillation of the material mixed with water and press extraction were compared. RESULTS: Bergapten wasnt extracted by ways of steam-input distillation and distillation of the material mixed with water. CONCLUSION: The steam distillation extraction can be taken to extract volatile oil from bergamot for protecting humans' skins.
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Aceites Volátiles/aislamiento & purificación , Plantas Medicinales/química , Rutaceae/química , Tecnología Farmacéutica/métodos , Cromatografía Líquida de Alta Presión , Cumarinas/análisis , Cumarinas/aislamiento & purificación , Frutas/química , Calor , Aceites Volátiles/química , Solventes/química , VaporRESUMEN
RING finger proteins and ubiquitination marks are widely involved in diverse aspects of growth and development, biological processes, and stress or environmental responses. As the smallest free-living photosynthetic eukaryote known so far, the green alga Ostreococus tauri has become an excellent model for investigating the origin of different gene families in the green lineage. Here, 65 RING domains in 65 predicted proteins were identified from O. tauri and on the basis of one or more substitutions at the metal ligand positions and spacing between them they were divided into eight canonical or modified types (RING-CH, -H2, -v, -C2, -C3HCHC2, -C2HC5, -C3GC3S, and -C2SHC4), in which the latter four were newly identified and might represent the intermediate states between RING domain and other similar domains, respectively. RING finger proteins were classified into eight classes based on the presence of additional domains, including RING-Only, -Plus, -C3H1, -PHD, -WD40, -PEX, -TM, and -DEXDc classes. These RING family genes usually lack introns and are distributed over 17 chromosomes. In addition, 29 RING-finger proteins in O. tauri share different degrees of homology with those in the model flowering plant Arabidopsis, indicating they might be necessary for the basic survival of free-living eukaryotes. Therefore, our results provide new insight into the general classification and evolutionary conservation of RING domain-containing proteins in O. tauri.
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Eucariontes/genética , Eucariontes/fisiología , Estudio de Asociación del Genoma Completo , Dominios RING Finger/genética , Secuencia de Aminoácidos , Organismos Acuáticos , Mapeo Cromosómico , Regulación de la Expresión Génica , FotosíntesisAsunto(s)
Membrana Celular/metabolismo , Quitina/metabolismo , Glicosilfosfatidilinositoles/metabolismo , Proteínas de la Membrana/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Secuencia de Aminoácidos , Arabidopsis/metabolismo , Glicosilfosfatidilinositol Diacilglicerol-Liasa/metabolismo , Mutación/genética , Proteínas de Plantas/química , Transporte de ProteínasRESUMEN
Natural organic matter (NOM) in a filtered river water from a water treatment plant was isolated and fractionated into six types of fractions. The aim of the work is to investigate the formation of the low molecular weight (LMW) oxidation by-products (i.e. aldehydes, ketones and ketoacids) after ferric hydroxide-catalyzed ozonation of individual NOM fractions. Results showed that catalytic ozonation could improve the reduction of the dissolved organic matter (DOC) and specific UV absorbance (SUVA) at 254 nm compared with ozonation alone. However, catalytic ozonation with ferric hydroxide could not produce less LMW oxidation by-products than ozonation. Hydrophobic neutral (HON) produced much higher yields of the LMW oxidation by-products than other fractions both during catalytic ozonation and ozonation alone, while the basic NOM fractions formed relatively lower productions of these by-products. Like the case of ozonation alone, the predominant contributors for the yields of aldehydes and ketoacids formed in catalytic ozonation were formaldehyde and pyruvic acid, respectively. Among these NOM fractions, HON produced the highest yields of the formaldehyde and pyruvic acid after catalytic ozonation. The yield of formaldehyde from HON was up to 71.6% of the total aldehydes and ketones, and the pyruvic acid concentration of HON was 78.6 microg/mg after catalytic ozonation. In addition, NOM fractions became more biodegradable after catalytic ozonation, because the percent of total LMW by-products carbon in the final DOC after catalytic ozonation was higher than ozonation alone.
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Compuestos Férricos/química , Compuestos Orgánicos/química , Ozono/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Aldehídos/química , Catálisis/efectos de los fármacos , Filtración , Cetonas/química , Compuestos Orgánicos/aislamiento & purificación , Oxidación-ReducciónRESUMEN
We report the synthesis, characterization, and covalent surface chemistry of "magnetomicelles", cross-linked, amphiphilic block-copolymer micelles that encapsulate superparamagnetic iron oxide nanoparticles. Because these composite nanostructures assemble spontaneously from solution by simultaneous desolvation of nanoparticle and amphiphilic poly(styrene(250)-block-acrylic acid(13)) components, explicit surface functionalization of the particles is not required, and the encapsulation method was applied to different magnetic nanoparticle sizes and compositions. TEM images of the magnetomicelles illustrated that the number of encapsulated particles could be dictated rationally by synthetic conditions. The magnetic properties of the particles were characterized by SQUID magnetometry and followed the general Langevin magnetic model for superparamagnetic materials. The micellar shells of these particles were functionalized using covalent chemistry that would not ordinarily be possible on the magnetic particle surface. As a result, this noncovalent approach provides a new route to technological applications of hydrophobic magnetic nanomaterials that lack appropriate conjugate surface chemistry.