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1.
Int J Mol Sci ; 25(11)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38892163

RESUMO

Extreme weather poses huge challenges for animals that must adapt to wide variations in environmental temperature and, in many cases, it can lead to the local extirpation of populations or even the extinction of an entire species. Previous studies have found that one element of amphibian adaptation to environmental stress involves changes in mitochondrial gene expression at low temperatures. However, to date, comparative studies of gene expression in organisms living at extreme temperatures have focused mainly on nuclear genes. This study sequenced the complete mitochondrial genomes of five Asian hylid frog species: Dryophytes japonicus, D. immaculata, Hyla annectans, H. chinensis and H. zhaopingensis. It compared the phylogenetic relationships within the Hylidae family and explored the association between mitochondrial gene expression and evolutionary adaptations to cold stress. The present results showed that in D. immaculata, transcript levels of 12 out of 13 mitochondria genes were significantly reduced under cold exposure (p < 0.05); hence, we put forward the conjecture that D. immaculata adapts by entering a hibernation state at low temperature. In H. annectans, the transcripts of 10 genes (ND1, ND2, ND3, ND4, ND4L, ND5, ND6, COX1, COX2 and ATP8) were significantly reduced in response to cold exposure, and five mitochondrial genes in H. chinensis (ND1, ND2, ND3, ND4L and ATP6) also showed significantly reduced expression and transcript levels under cold conditions. By contrast, transcript levels of ND2 and ATP6 in H. zhaopingensis were significantly increased at low temperatures, possibly related to the narrow distribution of this species primarily at low latitudes. Indeed, H. zhaopingensis has little ability to adapt to low temperature (4 °C), or maybe to enter into hibernation, and it shows metabolic disorder in the cold. The present study demonstrates that the regulatory trend of mitochondrial gene expression in amphibians is correlated with their ability to adapt to variable climates in extreme environments. These results can predict which species are more likely to undergo extirpation or extinction with climate change and, thereby, provide new ideas for the study of species extinction in highly variable winter climates.


Assuntos
Anuros , Genoma Mitocondrial , Filogenia , Animais , Anuros/genética , Anuros/fisiologia , Resposta ao Choque Frio/genética , Temperatura Baixa , Adaptação Fisiológica/genética , Regulação da Expressão Gênica
2.
Front Immunol ; 15: 1379853, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650937

RESUMO

Introduction: Macrophages are an important component of innate immunity and involved in the immune regulation of multiple diseases. The functional diversity and plasticity make macrophages to exhibit different polarization phenotypes after different stimuli. During tumor progression, the M2-like polarized tumor-associated macrophages (TAMs) promote tumor progression by assisting immune escape, facilitating tumor cell metastasis, and switching tumor angiogenesis. Our previous studies demonstrated that functional remodeling of TAMs through engineered-modifying or gene-editing provides the potential immunotherapy for tumor. However, lack of proliferation capacity and maintained immune memory of infused macrophages restricts the application of macrophage-based therapeutic strategies in the repressive tumor immune microenvironment (TIME). Although J2 retrovirus infection enabled immortalization of bone marrow-derived macrophages (iBMDMs) and facilitated the mechanisms exploration and application, little is known about the phenotypic and functional differences among multi kinds of macrophages. Methods: HE staining was used to detect the biosafety of iBMDMs, and real-time quantitative PCR, immunofluorescence staining, and ELISA were used to detect the polarization response and expression of chemokines in iBMDMs. Flow cytometry, scratch assay, real-time quantitative PCR, and crystal violet staining were used to analyze its phagocytic function, as well as its impact on tumor cell migration, proliferation, and apoptosis. Not only that, the inhibitory effect of iBMDMs on tumor growth was detected through subcutaneous tumor loading, while the tumor tissue was paraffin sectioned and flow cytometry was used to detect its impact on the tumor microenvironment. Results: In this study, we demonstrated iBMDMs exhibited the features of rapid proliferation and long-term survival. We also compared iBMDMs with RAW264.7 cell line and mouse primary BMDMs with in vitro and in vivo experiments, indicating that the iBMDMs could undergo the same polarization response as normal macrophages with no obvious cellular morphology changes after polarization. What's more, iBMDMs owned stronger phagocytosis and pro-apoptosis functions on tumor cells. In addition, M1-polarized iBMDMs could maintain the anti-tumor phenotypes and domesticated the recruited macrophages of receptor mice, which further improved the TIME and repressed tumor growth. Discussion: iBMDMs can serve as a good object for the function and mechanism study of macrophages and the optional source of macrophage immunotherapy.


Assuntos
Fenótipo , Animais , Camundongos , Microambiente Tumoral/imunologia , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/metabolismo , Macrófagos/imunologia , Proliferação de Células , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Apoptose , Fagocitose , Movimento Celular/imunologia
3.
Sheng Li Xue Bao ; 76(1): 128-136, 2024 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-38444138

RESUMO

Cardiovascular complications are the leading cause of death in diabetic patients. Among them, diabetic cardiomyopathy (DCM) is a type of specific cardiomyopathy excluding myocardial damage caused by hypertension and coronary heart disease. It is characterized by abnormal metabolism of cardiomyocytes and gradual decline of cardiac function. The clinical manifestations of DCM are impaired diastolic function in early stage and impaired systolic function in late stage. Eventually it developed into heart failure. Mitochondria are the main organelles that provide energy in cardiomyocytes. Mitochondrial dynamics refers to the dynamic process of mitochondrial fusion and fission, which is an important approach for mitochondrial quality control. Mitochondrial dynamics plays a crucial role in maintaining mitochondrial homeostasis and cardiac function. The proteins that regulate mitochondrial fission are mainly Drp1 and its receptors, Fis1, MFF, MiD49 and MiD51. The protein that performs mitochondrial outer membrane fusion is Mfn1/2, and the inner membrane fusion protein is Opa1. This paper reviews recent progress on mitochondrial dynamics in DCM. The main contents are as follows: mitochondrial dynamics imbalance in both type 1 and 2 DCM is manifested as increased fission and inhibited fusion. The molecular mechanism of the former is mainly associated with up-regulated Drp1 and down-regulated Opa1, while the molecular mechanism of the latter is mainly associated with up-regulated Drp1 and down-regulated Mfn1/2. Increased mitochondrial fission and inhibited fusion can lead to mitochondrial dysfunction and promote the development of DCM. The active ingredients of the traditional Chinese medicine such as punicalagin, paeonol and endogenous substance melatonin can improve mitochondrial function and alleviate the symptoms of DCM by inhibiting mitochondrial fission or promoting mitochondrial fusion. This article is helpful to further understand the role and mechanism of mitochondrial dynamics in DCM, and provide new treatment methods and intervention strategies for clinical DCM patients based on mitochondrial dynamics.


Assuntos
Diabetes Mellitus , Cardiomiopatias Diabéticas , Insuficiência Cardíaca , Humanos , Dinâmica Mitocondrial , Miocárdio , Homeostase , Proteínas de Membrana
4.
Cell Mol Biol Lett ; 29(1): 22, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38308199

RESUMO

INTRODUCTION: There is a high morbidity and mortality rate in mechanical trauma (MT)-induced hepatic injury. Currently, the molecular mechanisms underlying liver MT are largely unclear. Exploring the underlying mechanisms and developing safe and effective medicines to alleviate MT-induced hepatic injury is an urgent requirement. The aim of this study was to reveal the role of mitochondria-associated ER membranes (MAMs) in post-traumatic liver injury, and ascertain whether melatonin protects against MT-induced hepatic injury by regulating MAMs. METHODS: Hepatic mechanical injury was established in Sprague-Dawley rats and primary hepatocytes. A variety of experimental methods were employed to assess the effects of melatonin on hepatic injury, apoptosis, MAMs formation, mitochondrial function and signaling pathways. RESULTS: Significant increase of IP3R1 expression and MAMs formation were observed in MT-induced hepatic injury. Melatonin treatment at the dose of 30 mg/kg inhibited IP3R1-mediated MAMs and attenuated MT-induced liver injury in vivo. In vitro, primary hepatocytes cultured in 20% trauma serum (TS) for 12 h showed upregulated IP3R1 expression, increased MAMs formation and cell injury, which were suppressed by melatonin (100 µmol/L) treatment. Consequently, melatonin suppressed mitochondrial calcium overload, increased mitochondrial membrane potential and improved mitochondrial function under traumatic condition. Melatonin's inhibitory effects on MAMs formation and mitochondrial calcium overload were blunted when IP3R1 was overexpressed. Mechanistically, melatonin bound to its receptor (MR) and increased the expression of phosphorylated ERK1/2, which interacted with FoxO1 and inhibited the activation of FoxO1 that bound to the IP3R1 promoter to inhibit MAMs formation. CONCLUSION: Melatonin prevents the formation of MAMs via the MR-ERK1/2-FoxO1-IP3R1 pathway, thereby alleviating the development of MT-induced liver injury. Melatonin-modulated MAMs may be a promising therapeutic therapy for traumatic hepatic injury.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Melatonina , Animais , Ratos , Cálcio/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/tratamento farmacológico , Melatonina/farmacologia , Melatonina/uso terapêutico , Ratos Sprague-Dawley
5.
Nanomaterials (Basel) ; 14(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38251140

RESUMO

Magnetite nanoparticles (Fe3O4 NPs) have been intensively investigated because of their potential biomedical applications due to their high saturation magnetization. In this study, core-shell Fe3O4@C NPs (core = Fe3O4 NPs and shell = amorphous carbons, davg = 35.1 nm) were synthesized in an aqueous solution. Carbon coating terminated with hydrophilic -OH and -COOH groups imparted excellent biocompatibility and hydrophilicity to the NPs, making them suitable for biomedical applications. The Fe3O4@C NPs exhibited ideal relaxometric properties for T2 magnetic resonance imaging (MRI) contrast agents (i.e., high transverse and negligible longitudinal water proton spin relaxivities), making them exclusively induce only T2 relaxation. Their T2 MRI performance as contrast agents was confirmed in vivo by measuring T2 MR images in mice before and after intravenous injection.

6.
RSC Adv ; 13(46): 32381-32397, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37928839

RESUMO

Nanodiamonds (ND) are chemically inert and stable owing to their sp3 covalent bonding structure, but their surface sp2 graphitic carbons can be easily homogenized with diverse functional groups via oxidation, reduction, hydrogenation, amination, and halogenation. Further surface conjugation of NDs with hydrophilic ligands can boost their colloidal stability and functionality. In addition, NDs are non-toxic as they are made of carbons. They exhibit stable fluorescence without photobleaching. They also possess paramagnetic and ferromagnetic properties, making them suitable for use as a new type of fluorescence imaging (FI) and magnetic resonance imaging (MRI) probe. In this review, we focused on recently developed ND production methods, surface homogenization and functionalization methods, biocompatibilities, and biomedical imaging applications as FI and MRI probes. Finally, we discussed future perspectives.

7.
Animals (Basel) ; 13(19)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37835622

RESUMO

Unusual climates can lead to extreme temperatures. Fejervarya kawamurai, one of the most prevalent anurans in the paddy fields of tropical and subtropical regions in Asia, is sensitive to climate change. The present study focuses primarily on a single question: how do the 13 mitochondrial protein-coding genes (PCGs) respond to extreme temperature change compared with 25 °C controls? Thirty-eight genes including an extra tRNA-Met gene were identified and sequenced from the mitochondrial genome of F. kawamurai. Evolutionary relationships were assessed within the Dicroglossidae and showed that Dicroglossinae is monophyletic and F. kawamurai is a sister group to the clade of (F. multistriata + F. limnocharis). Transcript levels of mitochondrial genes in liver were also evaluated to assess responses to 24 h exposure to low (2 °C and 4 °C) or high (40 °C) temperatures. Under 2 °C, seven genes showed significant changes in liver transcript levels, among which transcript levels of ATP8, ND1, ND2, ND3, ND4, and Cytb increased, respectively, and ND5 decreased. However, exposure to 4 °C for 24 h was very different in that the expressions of ten mitochondrial protein-coding genes, except ND1, ND3, and Cytb, were significantly downregulated. Among them, the transcript level of ND5 was most significantly downregulated, decreasing by 0.28-fold. Exposure to a hot environment at 40 °C for 24 h resulted in a marked difference in transcript responses with strong upregulation of eight genes, ranging from a 1.52-fold increase in ND4L to a 2.18-fold rise in Cytb transcript levels, although COI and ND5 were reduced to 0.56 and 0.67, respectively, compared with the controls. Overall, these results suggest that at 4 °C, F. kawamurai appears to have entered a hypometabolic state of hibernation, whereas its mitochondrial oxidative phosphorylation was affected at both 2 °C and 40 °C. The majority of mitochondrial PCGs exhibited substantial changes at all three temperatures, indicating that frogs such as F. kawamurai that inhabit tropical or subtropical regions are susceptible to ambient temperature changes and can quickly employ compensating adjustments to proteins involved in the mitochondrial electron transport chain.

8.
Animals (Basel) ; 13(10)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37238023

RESUMO

Hyla sanchiangensis (Anura: Hylidae) is endemic to China and is distributed across Anhui, Zhejiang, Fujian, Guangdong, Guangxi, Hunan, and Guizhou provinces. The mitogenomes of H. sanchiangensis from two different sites (Jinxiu, Guangxi, and Wencheng, Zhejiang) were sequenced. Phylogenetic analyses were conducted, including 38 mitogenomes of Hylidae from the NCBI database, and assessed the phylogenetic relationship of H. sanchiangensis within the analyzed dataset. Two mitogenomes of H. sanchiangensis showed the typical mitochondrial gene arrangement with 13 protein-coding genes (PCGs), two ribosomal RNA genes (12S rRNA and 16S rRNA), 22 transfer RNA (tRNA) genes, and one non-coding control region (D-loop). The lengths of the 12S rRNA and 16S rRNA genes from both samples (Jinxiu and Wencheng) were 933 bp and 1604 bp, respectively. The genetic distance (p-distance transformed into percent) on the basis of the mitogenomes (excluding the control region) of the two samples was calculated as 4.4%. Hyla sanchiangensis showed a close phylogenetic relationship with the clade of (H. annectans + H. tsinlingensis), which was supported by ML and BI analyses. In the branch-site model, five positive selection sites were found in the clade of Hyla and Dryophytes: Cytb protein (at position 316), ND3 protein (at position 85), and ND5 protein (at position 400) have one site, respectively, and two sites in ND4 protein (at positions 47 and 200). Based on the results, we hypothesized that the positive selection of Hyla and Dryophytes was due to their experience of cold stress in historical events, but more evidence is needed to support this conclusion.

10.
Minim Invasive Ther Allied Technol ; 32(3): 91-97, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36762759

RESUMO

OBJECTIVE: To develop an alarm device for the mechanical compression device displacement (MCD), and further evaluate its effectiveness in clinical use. MATERIAL AND METHODS: The alarm device is mainly composed of buzzer, indicator light, magnetic sheet. This is a prospective randomized and controlled study. Four hundred patients who met the inclusion/exclusion criteria were included and randomly assigned to two groups (MCD group vs alarm + MCD group). The primary outcome measures were the sensitivity and specificity of the alarm device to detect MCD displacement, time to hemostasis (TTH), time to ambulation (TTA), time to hospital discharge (TTHD), hospital costs (HC), complication rates, and patient satisfaction. RESULTS: The sensitivity and specificity of the alarm device in detecting MCD displacement were 94.44% and 88.46%, respectively. The study group achieved shorter TTH (p = .034), shorter TTA (p = .021), lower complication rates (p = .025), and better patients' satisfaction (p < .001) compared to the control group. However, no significant difference was observed in TTHD (p = .361) and HC (p = .583). CONCLUSION: The alarm device is highly sensitive in detecting MCD displacement, while achieving better clinical outcomes compared with artificial monitoring.


Assuntos
Artéria Femoral , Técnicas Hemostáticas , Humanos , Artéria Femoral/cirurgia , Estudos Prospectivos , Hemostasia , Punções , Resultado do Tratamento
11.
Front Microbiol ; 13: 895779, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36051755

RESUMO

Transcription and replication of the influenza A virus (IAV) genome take place in the nucleus of infected cells, which rely on host factors to aid viral ribonucleoprotein (vRNP) to cross the nuclear pore complex (NPC) and complete the bidirectional nucleocytoplasmic trafficking. Here, we showed that nucleoporin 85 (NUP85), a component of NPC, interacted with RNP subunits polymerase basic 1 (PB1) and polymerase basic 2 (PB2) in an RNA-dependent manner during IAV infection. Knockdown of NUP85 delayed the nuclear import of vRNP, PB1 and PB2, inhibiting polymerase activity and ultimately suppressing viral replication. Further analysis revealed that NUP85 assisted the binding of PB1 to nuclear transport factor Ran-binding protein 5 (RanBP5) and the binding of PB2 to nuclear transport factor importin α1 and importin α7. We also found that NUP85 expression was downregulated upon IAV infection. Together, our study demonstrated that NUP85 positively regulated IAV infection by interacting with viral PB1 and PB2, which may provide new insight into the process of vRNP nuclear import and a novel target for effective antivirals.

12.
World J Clin Cases ; 10(22): 7906-7912, 2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-36158491

RESUMO

BACKGROUND: Latamoxef shows excellent antibacterial activity against anaerobic bacteria such as Bacteroides fragilis. Reports of thrombocytopenic toxicity of latamoxef are limited. This report presents a case of severe thrombocytopenia possibly induced by latamoxef, an infrequent adverse drug reaction in a young patient with tuberculosis and Crohn's disease in China. CASE SUMMARY: We reported a case of severe thrombocytopenia induced by latamoxef in a 28-year-old man with tuberculosis and Crohn's disease. On admission, the patient presented with a cough productive of bloody sputum, a chest computed tomogram suggested scattered mottled, high-density shadows in both lungs. Laboratory tests indicated a platelet count of 140000/µL. Considered a pulmonary bacterial infection, the patient received anti-infection therapy with latamoxef (dose: 2.0 g) intravenously Q12h. On the 9th day of treatment, the platelet count decreased to 44000/µL. On the 12th day, scattered purpura and ecchymosis appeared on the patient's limbs and trunk, and the platelet count decreased to 9000/µL after latamoxef treatment for 15 d. Three days after discontinuation of latamoxef, the platelet count recovered to 157000/µL, and the area of scattered purpura and ecchymosis on the limbs and trunk decreased. The platelet counts remained in the normal range, and no thrombocytopenia was found at follow-up 15 mo after discharge. CONCLUSION: For patients treated with latamoxef, platelet counts should be carefully followed, and caregivers should be vigilant for the appearance of scattered ecchymosis.

13.
Artigo em Inglês | MEDLINE | ID: mdl-35958918

RESUMO

The overuse of antibiotics has contributed to the emergence of multidrug-resistant bacteria, which poses a challenging task for clinical therapy. Thus, new agents with antibiotic efficacy against multidrug-resistant infections are needed. The traditional Dong ethnic minority medicines have emerged as a new source for prodrug selection. Among them, Madeng'ai (PotentillafreynianaBornm) is widely used by the folk for anti-infection and wound healing, although the mechanisms remain unclear. In this study, the antimicrobial activities of Dong medicine Madeng'ai were evaluated both in vitro and in vivo. S. aureus, E. coli, E. faecalis, P. aeruginosa, K. pneumoniae, and A. baumannii were cultured in LB media, different concentrations of Madeng'ai powder solution were added to the LB agar plates to evaluate minimal inhibitory concentration. An animal study was performed on a mouse excisional wound model combined with bacterial solution injection in the wound area. After Madeng'ai or PBS treatment, hematoxylin and eosin analysis were used for pathological analysis of skin tissues from the infected area. Madeng'ai powder solution over 2 mg/mL concentration completely inhibited E. coli growth. At 4.0 mg/mL, Madeng'ai significantly inhibited the growth of E. faecalis, Pseudomonas aeruginosa (PAE), Klebsiella pneumoniae, and Acinetobacter baumannii. The mouse model revealed that Madeng'ai could suppress the growth of MRSA and PAE and accelerate healing of cutaneous wounds. Madeng'ai, a newly discovered Dong ethnic minority medicine possesses considerable antimicrobial activity against both human normal pathogenic bacteria and multiresistance bacteria such as Pseudomonas aeruginosa, S. aureus, and Acinetobacter baumannii. Therefore, Madeng'ai has great potential for further study and clinical application.

14.
Cell Death Discov ; 8(1): 353, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35941127

RESUMO

We explored the potential activity of compound 16 (Cpd16), a novel small molecule Nrf2 activator, in hydrogen peroxide (H2O2)-stimulated osteoblasts. In the primary murine/human osteoblasts and MC3T3-E1 murine osteoblastic cells, Cpd16 treatment at micro-molar concentrations caused disassociation of Keap1-Nrf2 and Nrf2 cascade activation. Cpd16 induced stabilization of Nrf2 protein and its nuclear translocation, thereby increasing the antioxidant response elements (ARE) reporter activity and Nrf2 response genes transcription in murine and human osteoblasts. Significantly, Cpd16 mitigated oxidative injury in H2O2-stimulited osteoblasts. H2O2-provoked apoptosis as well as programmed necrosis in osteoblasts were significantly alleviated by the novel Nrf2 activator. Cpd16-induced Nrf2 activation and osteoblasts protection were stronger than other known Nrf2 activators. Dexamethasone- and nicotine-caused oxidative stress and death in osteoblasts were attenuated by Cpd16 as well. Cpd16-induced osteoblast cytoprotection was abolished by Nrf2 short hairpin RNA or knockout, but was mimicked by Keap1 knockout. Keap1 Cys151S mutation abolished Cpd16-induced Nrf2 cascade activation and osteoblasts protection against H2O2. Importantly, weekly Cpd16 administration largely ameliorated trabecular bone loss in ovariectomy mice. Together, Cpd16 alleviates H2O2-induced oxidative stress and death in osteoblasts by activating Nrf2 cascade.

15.
Pharmaceutics ; 14(7)2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35890353

RESUMO

Hydrophilic and biocompatible PAA-coated ultrasmall Gd2O3 nanoparticles (davg = 1.7 nm) were synthesized and conjugated with tumor-targeting ligands, i.e., cyclic arginylglycylaspartic acid (cRGD) and/or folic acid (FA). FA-PAA-Gd2O3 and cRGD/FA-PAA-Gd2O3 nanoparticles were successfully applied in U87MG tumor-bearing mice for tumor imaging using T1 magnetic resonance imaging (MRI). cRGD/FA-PAA-Gd2O3 nanoparticles with multiple tumor-targeting ligands exhibited higher contrasts at the tumor site than FA-PAA-Gd2O3 nanoparticles with mono tumor-targeting ligands. In addition, the cRGD/FA-PAA-Gd2O3 nanoparticles exhibited higher contrasts in all organs, especially the aorta, compared with those of the FA-PAA-Gd2O3 nanoparticles, because of the blood cell hitchhiking effect of cRGD in the cRGD/FA-PAA-Gd2O3 nanoparticles, which prolonged their circulation in the blood.

16.
Nanomaterials (Basel) ; 12(9)2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35564300

RESUMO

Water proton spin relaxivities, colloidal stability, and biocompatibility of nanoparticle magnetic resonance imaging (MRI) contrast agents depend on surface-coating ligands. In this study, hydrophilic and biocompatible polyethylenimines (PEIs) of different sizes (Mn = 1200 and 60,000 amu) were used as surface-coating ligands for ultrasmall holmium oxide (Ho2O3) nanoparticles. The synthesized PEI1200- and PEI60000-coated ultrasmall Ho2O3 nanoparticles, with an average particle diameter of 2.05 and 1.90 nm, respectively, demonstrated low cellular cytotoxicities, good colloidal stability, and appreciable transverse water proton spin relaxivities (r2) of 13.1 and 9.9 s-1mM-1, respectively, in a 3.0 T MR field with negligible longitudinal water proton spin relaxivities (r1) (i.e., 0.1 s-1mM-1) for both samples. Consequently, for both samples, the dose-dependent contrast changes in the longitudinal (R1) and transverse (R2) relaxation rate map images were negligible and appreciable, respectively, indicating their potential as efficient transverse T2 MRI contrast agents in vitro.

17.
Cell Oncol (Dordr) ; 45(3): 447-462, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35543858

RESUMO

BACKGROUND: Abnormal expression of long non-coding RNAs (lncRNAs) has been associated with the initiation and progression of hepatocellular carcinoma but, as yet, the clinicopathologic significance and potential role of Linc02154 in HCC remains to be determined. Here, we aimed to investigate the potential role and mode of action of Linc02154 in HCC. METHODS: The expression of Linc02154 in 20 pairs of HCC/normal tissues and 7 HCC cell lines was detected by qRT-PCR. The localization of Linc02154 in HCC cells was detected using fluorescence in situ hybridization and nuclear-plasma separation assays. MTS, EdU incorporation, colony formation, flow cytometry, scratch wound-healing and transwell assays were performed to assess the role of Linc02154 in HCC cell proliferation, migration and invasion in vitro, and BALB/c nude mice xenografts were used to evaluate its role in vivo. RNA sequencing and Western blotting were used to evaluate the regulatory effect of Linc02154 on SPC24 gene expression. A dual-luciferase reporter assay was used to assess a putative interaction of Linc02154 with the SPC24 promoter. RESULTS: We identified a new lncRNA, Linc02154, that is highly expressed in HCC cells and tissues of patients with a poor overall survival. Functional experiments revealed that exogenous Linc02154 expression in MHCC-97H and SK-Hep1 cells promoted their proliferation, migration and invasion in vitro and their tumorigenesis in vivo. Using a dual luciferase reporter assay we found that Linc02154 can enhance SPC24 promoter (-500 bp ~ -1000 region) activity. Exogenous over-expression of Linc02154 led to up-regulation of SPC24 by activating PI3K/AKT and its downstream signals, including cell cycle progression and EMT-associated gene expression. CONCLUSION: Our data suggest that Linc02154 may serve as a valuable biomarker of HCC and as a potential therapeutic target.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteínas Associadas aos Microtúbulos , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , RNA Longo não Codificante , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Xenoenxertos , Humanos , Hibridização in Situ Fluorescente , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Nus , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Transdução de Sinais/genética
19.
Int J Mol Sci ; 23(3)2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35163714

RESUMO

Owing to a higher demand for glucosamine (GlcN) in metabolic processes in tumor cells than in normal cells (i.e., GlcN effects), tumor imaging in magnetic resonance imaging (MRI) can be highly improved using GlcN-conjugated MRI contrast agents. Here, GlcN was conjugated with polyacrylic acid (PAA)-coated ultrasmall gadolinium oxide nanoparticles (UGONs) (davg = 1.76 nm). Higher positive (brighter or T1) contrast enhancements at various organs including tumor site were observed in human brain glioma (U87MG) tumor-bearing mice after the intravenous injection of GlcN-PAA-UGONs into their tail veins, compared with those obtained with PAA-UGONs as control, which were rapidly excreted through the bladder. Importantly, the contrast enhancements of the GlcN-PAA-UGONs with respect to those of the PAA-UGONs were the highest in the tumor site owing to GlcN effects. These results demonstrated that GlcN-PAA-UGONs can serve as excellent T1 MRI contrast agents in tumor imaging via GlcN effects.


Assuntos
Nanopartículas , Neoplasias , Resinas Acrílicas , Animais , Meios de Contraste , Gadolínio , Glucosamina , Imageamento por Ressonância Magnética/métodos , Camundongos
20.
ACS Omega ; 7(3): 2533-2553, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35097254

RESUMO

157Gd (natural abundance = 15.7%) has the highest thermal neutron capture cross section (σ) of 254,000 barns (1 barn = 10-28 m2) among stable (nonradioactive) isotopes in the periodic table. Another stable isotope, 155Gd (natural abundance = 14.8%), also has a high σ value of 60,700 barns. These σ values are higher than that of 10B (3840 barns, natural abundance = 19.9%), which is currently used as a neutron-absorbing isotope for boron neutron capture therapy agents. Energetic particles such as electrons and γ-rays emitted from Gd-isotopes after neutron beam absorption kill cancer cells by damaging DNAs inside cancer-cell nuclei without damaging normal cells if Gd-chemicals are positioned in cancer cells. To date, various Gd-chemicals such as commercial Gd-chelates used as magnetic resonance imaging contrast agents, modified Gd-chelates, nanocomposites containing Gd-chelates, fullerenes containing Gd, and solid-state Gd-nanoparticles have been investigated as gadolinium neutron capture therapy (GdNCT) agents. All GdNCT agents had exhibited cancer-cell killing effects, and the degree of the effects depended on the GdNCT agents used. This confirms that GdNCT is a promising cancer therapeutic technique. However, the commercial Gd-chelates were observed to be inadequate in clinical use because of their low accumulation in cancer cells due to their extracellular and noncancer targeting properties and rapid excretion. The other GdNCT agents exhibited higher accumulation in cancer cells, compared to Gd-chelates; consequently, they demonstrated higher cancer-cell killing effects. However, they still displayed limitations such as poor specificity to cancer cells. Therefore, continuous efforts should be made to synthesize GdNCT agents suitable in clinical applications. Herein, the principle of GdNCT, current status of GdNCT agents, and general design strategy for GdNCT agents in clinical use are discussed and reviewed.

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