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1.
Biomacromolecules ; 25(3): 1371-1390, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38346318

RESUMO

The emergence of photoinduced energy/electron transfer-reversible addition-fragmentation chain transfer polymerization (PET-RAFT) not only revolutionized the field of photopolymerization but also accelerated the development of porphyrin-based photocatalysts and their analogues. The continual expansion of the monomer family compatible with PET-RAFT polymerization enhances the range of light radiation that can be harnessed, providing increased flexibility in polymerization processes. Furthermore, the versatility of PET-RAFT polymerization extends beyond its inherent capabilities, enabling its integration with various technologies in diverse fields. This integration holds considerable promise for the advancement of biomaterials with satisfactory bioapplications. As researchers delve deeper into the possibilities afforded by PET-RAFT polymerization, the collaborative efforts of individuals from diverse disciplines will prove invaluable in unleashing its full potential. This Review presents a concise introduction to the fundamental principles of PET-RAFT, outlines the progress in photocatalyst development, highlights its primary applications, and offers insights for future advancements in this technique, paving the way for exciting innovations and applications.


Assuntos
Porfirinas , Humanos , Polimerização , Tomografia por Emissão de Pósitrons
2.
Eur Radiol ; 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374482

RESUMO

OBJECTIVES: To evaluate the additional advantages of integrating contrast-enhanced ultrasound (CEUS) into the Ovarian-Adnexal Reporting and Data System (O-RADS) ultrasound (US) for the characterization of adnexal lesions with solid components. MATERIALS AND METHODS: This prospective multicenter study recruited women suspected of having adnexal lesions with solid components between September 2021 and December 2022. All patients scheduled for surgery underwent preoperative CEUS and US examinations. The lesions were categorized according to the O-RADS US system, and quantitative CEUS indexes were recorded. Pathological results served as the reference standard. Univariable and multivariable analyses were performed to identify risk factors for malignancy in adnexal lesions with solid components. Receiver operating characteristic (ROC) curve analysis was employed to assess diagnostic performance. RESULTS: A total of 180 lesions in 175 women were included in the study. Among these masses, 80 were malignant and 100 were benign. Multivariable analysis revealed that serum CA-125, the presence of acoustic shadowing, and peak intensity (PI) ratio (PImass/PIuterus) of solid components on CEUS were independently associated with adnexal malignancy. The modified CEUS risk stratification model demonstrated superior diagnostic value in assessing adnexal lesions with solid components compared to O-RADS US (AUC: 0.91 vs 0.78, p < 0.001) and exhibited comparable performance to the Assessment of Different NEoplasias in the adnexa (ADNEX) model (AUC 0.91 vs 0.86, p = 0.07). CONCLUSION: Our findings underscore the potential value of CEUS as an adjunctive tool for enhancing the precision of diagnostic evaluations of O-RADS US. CLINICAL RELEVANCE STATEMENT: The promising performance of the modified CEUS risk stratification model suggests its potential to mitigate unnecessary surgeries in the characterization of adnexal lesions with solid components. KEY POINTS: • The additional value of CEUS to O-RADS US in distinguishing between benign and malignant adnexal lesions with solid components requires further evaluation. • The modified CEUS risk stratification model displayed superior diagnostic value and specificity in characterizing adnexal lesions with solid components when compared to O-RADS US. • The inclusion of CEUS demonstrated potential in reducing the need for unnecessary surgeries in the characterization of adnexal lesions with solid components.

3.
Cell Mol Biol Lett ; 29(1): 46, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561669

RESUMO

BACKGROUND: Small extracellular vesicles (sEV) are closely associated with the development and metastasis of many types of mammalian cancer. Glycoconjugates are highly expressed on sEV and play important roles in sEV biogenesis and their interaction with other cells. However, the study on vesicular glycoconjugates are far behind proteins and nucleic acids. Especially, the functions of sialic acids which are the terminal components of glycoconjugates, are poorly understood in sEV. METHODS: Sialic acid levels on sEV from plasma and bladder cancer cells were determined by ELISA and lectin blotting. Effects of sialylation on sEV uptake were determined by flow cytometry. Vesicular glycoproteins bearing sialic acids responsible for sEV uptake was identified by proteomics and density gradient centrifugation, and their site-specific sialylation functions were assayed by N-glycosylation site mutation. Effects of integrin ß1 bearing sialic acids on the pro-metastatic function of sEV in vivo were explored using Balb/c nu/nu mice. RESULTS: (1) Increased sialic acid levels were observed in sEV from malignant bladder cancer cells. (2) Elimination of sialic acids on sEV impaired sEV uptake by recipient cells. (3) Vesicular integrin ß1 bearing sialic acids was identified to play a key role in sEV uptake. (4) Desialylation of the hybrid domain of vesicular integrin ß1 inhibited its binding to matrix fibronectin, and reduced sEV entry into recipient cells. (5) Sialylation on integrin ß1 affected pro-metastatic function of sEV in Balb/c nu/nu mice. CONCLUSIONS: Taken together, our findings indicate important functional roles of sialic acids in sEV uptake and reprogramming plasticity of surrounding normal epithelial cells.


Assuntos
Vesículas Extracelulares , Neoplasias da Bexiga Urinária , Animais , Camundongos , Vesículas Extracelulares/metabolismo , Glicoconjugados , Integrina beta1/metabolismo , Mamíferos , Ácido N-Acetilneuramínico/metabolismo , Ácidos Siálicos/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-38430161

RESUMO

Objective: To report the efficacy and safety of combination therapy with selinexor, palbociclib, pembrolizumab, and umbilical cord blood NK cells for advanced hepatocellular carcinoma (HCC).Advanced HCC has a poor prognosis and limited effective treatment options. Exploring personalized combination treatment strategies is critically important for improving outcomes in patients with advanced HCC. This study aims to provide preliminary evaluation of the clinical effectiveness and safety of this combination regimen in this high-risk population, and lay the groundwork for larger studies to bring more treatment choices to patients with advanced HCC. Methods: A 67-year-old male patient with advanced HCC and multiple metastases was treated with palbociclib 75mg on days 1-14 of a 28-day cycle, pembrolizumab 200mg intravenous infusion, selinexor 40mg weekly, and umbilical cord blood NK cell (12×109 cells) infusion on days 1, 14, 28 and 42. Imaging examinations and tumor marker detection were performed before and after two cycles of treatment to evaluate response. Results: After two cycles of combination treatment, follow-up PET-CT showed partial response with the liver tumors reduced in size by approximately 60%, lung metastases reduced by approximately 90%, and FDG uptake decreased more than 90% in lymph nodes and bone metastases. The AFP level decreased compared to baseline. Liver function tests including albumin, bilirubin and prothrombin time improved. The patient's performance status also improved from ECOG 2 to ECOG 1. Conclusions: This case report describes preliminary signals that the combination of selinexor, palbociclib, pembrolizumab, and umbilical cord blood NK cells may warrant further investigation for the treatment of advanced HCC. Objective response was observed based on standardized response criteria. However, due to the limitations of a single-arm case study design, definitive conclusions cannot be drawn regarding the efficacy or safety profile of this personalized combination approach. Larger and more robust clinical trials are needed to fully validate if this treatment strategy can achieve clinical benefit for advanced HCC. Future studies should aim to elucidate potential biomarkers that may help identify patients most likely to respond to this combination regimen. Exploring optimal patient selection criteria could also help maximize clinical benefit. Further research is warranted to continue exploring precision medicine combinations involving immunotherapy, targeted agents and cellular therapies for advanced HCC.

5.
Curr Issues Mol Biol ; 45(5): 4214-4227, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37232737

RESUMO

(1) Background: Many studies have shown that microgravity experienced by astronauts or long-term bedridden patients results in increased oxidative stress and bone loss. Low-molecular-weight chondroitin sulfates (LMWCSs) prepared from intact chondroitin sulfate (CS) have been demonstrated to possess good antioxidant and osteogenic activities in vitro. This study aimed to assess the antioxidant activity of the LMWCSs in vivo and evaluate their potential in preventing microgravity-induced bone loss. (2) Methods: we used hind limb suspension (HLS) mice to simulate microgravity in vivo. We investigated the effects of LMWCSs against oxidative stress damage and bone loss in HLS mice and compared the findings with those of CS and a non-treatment group. (3) Results: LMWCSs reduced the HLS-induced oxidative stress level, prevented HLS-induced alterations in bone microstructure and mechanical strength, and reversed changes in bone metabolism indicators in HLS mice. Additionally, LMWCSs downregulated the mRNA expression levels of antioxidant enzyme- and osteogenic-related genes in HLS mice. The results showed that overall effect of LMWCSs was better than that of CS. (4) Conclusions: LMWCSs protect against the bone loss caused by simulated microgravity, which may be related to their ability to reduce oxidative stress. LMWCSs can be envisaged as potential antioxidants and bone loss protective agents in microgravity.

6.
Biomacromolecules ; 24(5): 2301-2313, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37067047

RESUMO

The aggregation-caused quenching, premature drug release, and hypoxia-caused resistance of photodynamic therapy (PDT) are challenges in the design and preparation of novel porphyrin-containing photosensitizers. In this work, a series of block copolymers consisting of a hydrophilic glycopolymer block and a porphyrin-containing hydrophobic block were prepared via reversible addition-fragmentation chain transfer polymerization. The polymeric photosensitizers generate singlet oxygen and excellent PDT against HepG2, which can be strengthened by the addition of cholic acid. To combine with chemotherapy, doxorubicin (Dox) was successfully loaded into copolymers, which were observed to be more phototoxic, indicating that the therapeutic benefit of the synergistic effect of PDT and chemotherapy is better than their simple combination. The sugar-cell-specific interaction of galactose-containing photosensitizers results in a stronger mean fluorescent index (MFI) intracellular uptake in HepG2 cells in vitro compared to L929 and MCF-7 cells. These polymeric nanoplatforms present a versatile and effective avenue for developing synergistic therapy for cancer treatment.


Assuntos
Nanopartículas , Fotoquimioterapia , Porfirinas , Humanos , Fármacos Fotossensibilizantes/química , Fotoquimioterapia/métodos , Ácido Cólico/farmacologia , Nanopartículas/química , Doxorrubicina/farmacologia , Doxorrubicina/química , Polímeros/farmacologia , Polímeros/química , Porfirinas/química , Linhagem Celular Tumoral
7.
Sensors (Basel) ; 23(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37177552

RESUMO

Herein, an ultra-sensitive and facile electrochemical biosensor for procalcitonin (PCT) detection was developed based on NiCoP/g-C3N4 nanocomposites. Firstly, NiCoP/g-C3N4 nanocomposites were synthesized using hydrothermal methods and then functionalized on the electrode surface by π-π stacking. Afterward, the monoclonal antibody that can specifically capture the PCT was successfully linked onto the surface of the nanocomposites with a 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and N-Hydroxysuccinimide (NHS) condensation reaction. Finally, the modified sensor was employed for the electrochemical analysis of PCT using differential Pulse Voltammetry(DPV). Notably, the larger surface area of g-C3N4 and the higher electron transfer capacity of NiCoP/g-C3N4 endow this sensor with a wider detection range (1 ag/mL to 10 ng/mL) and an ultra-low limit of detection (0.6 ag/mL, S/N = 3). In addition, this strategy was also successfully applied to the detection of PCT in the diluted human serum sample, demonstrating that the developed immunosensors have the potential for application in clinical testing.


Assuntos
Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Nanocompostos , Humanos , Pró-Calcitonina , Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Técnicas Eletroquímicas/métodos , Limite de Detecção , Ouro
8.
Genes Cells ; 26(9): 684-697, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34086379

RESUMO

Autophagy in dopamine (DA) neurons is concerned to be associated with Parkinson's disease (PD), but the detailed mechanism remains unknown. Herein, we aimed to investigate the function of microRNA (miR)-29c-3p in autophagy in PD models. Intraperitoneal injection of MPTP (20 mg/kg) was given to C57BL/6 mice to establish PD mouse model. SH-SY5Y cells were treated with MPP+ (1 mmol/L) to establish in vitro PD model. The results indicated that in the substantia nigra pars compacta (SNpc) DA neurons of PD mice, autophagy was activated accompanied by down-regulated miR-29c-3p and up-regulated ten-eleven translocation 2 (TET2) expression. Up-regulation of miR-29c-3p inhibited TET2 expression and SNpc (including DA neurons) autophagy in PD mice. In vitro PD model confirmed that MPP+ treatment markedly down-regulated miR-29c-3p expression and up-regulated TET2 expression in SH-SY5Y cells in a dose/time-dependent manner. Moreover, miR-29c-3p up-regulation also inhibited autophagy and TET2 expression in vitro. Additionally, TET2 was proved to be targeted and down-regulated by miR-29c-3p. TET2 knockdown inhibited MPP+ -induced autophagy, whereas TET2 over-expression reversed the effects of miR-29c-3p over-expression on SH-SY5Y cell autophagy. Overall, miR-29c-3p over-expression inhibits autophagy in PD models, which may be mediated by TET2. Our finding may provide new insights for regulating autophagy to improve PD progression.


Assuntos
Autofagia , Proteínas de Ligação a DNA/genética , Dioxigenases/genética , Intoxicação por MPTP/metabolismo , MicroRNAs/metabolismo , Animais , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Dioxigenases/metabolismo , Humanos , Intoxicação por MPTP/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Neurônios/metabolismo
9.
New Phytol ; 234(5): 1639-1653, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35243647

RESUMO

The root economics space (RES) is multidimensional and largely shaped by belowground biotic and abiotic influences. However, how root-fungal symbioses and edaphic fertility drive this complexity remains unclear. Here, we measured absorptive root traits of 112 tree species in temperate and subtropical forests of China, including traits linked to functional differences between arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) hosts. Our data, from known mycorrhizal tree species, revealed a 'fungal-symbiosis' dimension distinguishing AM from ECM species. This divergence likely resulted from the contrasting mycorrhizal evolutionary development of AM vs ECM associations. Increased root tissue cortical space facilitates AM symbiosis, whereas increased root branching favours ECM symbiosis. Irrespective of mycorrhizal type, a 'root-lifespan' dimension reflecting aspects of root construction cost and defence was controlled by variation in specific root length and root tissue density, which was fully independent of root nitrogen content. Within this function-based RES, we observed a substantial covariation of axes with soil phosphorus and nitrate levels, highlighting the role played by these two axes in nutrient acquisition and conservation. Overall, our findings demonstrate the importance of evolved mycorrhizal symbiosis pathway and edaphic fertility in framing the RES, and provide theoretical and mechanistic insights into the complexity of root economics.


Assuntos
Micorrizas , Fertilidade , Raízes de Plantas/metabolismo , Solo , Microbiologia do Solo , Simbiose , Árvores
10.
J Environ Manage ; 317: 115468, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35660828

RESUMO

Giant ragweed (Ambrosia trifida L.), an invasive weed, has an expanding distribution area and has recently started to spread in grasslands. This unusual event threatens grasslands worldwide. In this study, we aimed to evaluate the changes in the grassland soil seed banks caused by the giant ragweed invasion in Yili Valley, Xinjiang, China. Using the space-for-time substitution approach, we compared and quantified the soil seed bank communities in a grassland over eight years following giant ragweed invasion and after its removal. The results showed that the duration of invasion determined whether giant ragweed might pose a significant threat to the native seed bank community. Four years after the invasion, the in-site seed bank density of native community significantly decreased (30.44%), while the relative coverage of giant ragweed aboveground reached 83.75%. Furthermore, the species richness in the seed bank decreased significantly (12.36%), while the relative coverage of giant ragweed reached 100% six years after the invasion. Eight years after the invasion, the seed bank density and species richness of the native community decreased by 83.28% and 39.33%, respectively, whereby the seed banks tended to be homogeneous. After the removal of giant ragweed, the potential for regeneration was limited by the residual seed bank densities of the native community. Although the native seed bank density had increased significantly after three years of restoration, new growth was dominated by weedy species, rather than by the distinctive components of the grassland habitat. Our study clarifies the process by which giant ragweed causes damage to grasslands and serves as a reference for grassland restoration and management efforts.


Assuntos
Banco de Sementes , Solo , Ambrosia , Ecossistema , Pradaria , Sementes
11.
BMC Genomics ; 22(1): 299, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33892633

RESUMO

BACKGROUND: Tribenuron methyl (TBM) is an herbicide that inhibits sulfonylurea acetolactate synthase (ALS) and is one of the most widely used broad-leaved herbicides for crop production. However, soil residues or drifting of the herbicide spray might affect the germination and growth of rapeseed, Brassica napus, so it is imperative to understand the response mechanism of rape to TBM during germination. The aim of this study was to use transcriptome analysis to reveal the gene responses in herbicide-tolerant rapeseed to TBM stress during seed germination. RESULTS: 2414, 2286, and 1068 differentially expressed genes (DEGs) were identified in TBM-treated resistant vs sensitive lines, treated vs. control sensitive lines, treated vs. control resistant lines, respectively. GO analysis showed that most DEGs were annotated to the oxidation-reduction pathways and catalytic activity. KEGG enrichment was mainly involved in plant-pathogen interactions, α-linolenic acid metabolism, glucosinolate biosynthesis, and phenylpropanoid biosynthesis. Based on GO and KEGG enrichment, a total of 137 target genes were identified, including genes involved in biotransferase activity, response to antioxidant stress and lipid metabolism. Biotransferase genes, CYP450, ABC and GST, detoxify herbicide molecules through physical or biochemical processes. Antioxidant genes, RBOH, WRKY, CDPK, MAPK, CAT, and POD regulate plant tolerance by transmitting ROS signals and triggering antioxidant enzyme expression. Lipid-related genes and hormone-related genes were also found, such as LOX3, ADH1, JAZ6, BIN2 and ERF, and they also played an important role in herbicide resistance. CONCLUSIONS: This study provides insights for selecting TBM-tolerant rapeseed germplasm and exploring the molecular mechanism of TBM tolerance during germination.


Assuntos
Brassica napus , Herbicidas , Sulfonatos de Arila , Brassica napus/genética , Perfilação da Expressão Gênica , Germinação/genética , Herbicidas/toxicidade , Sementes , Transcriptoma
12.
Mol Med ; 27(1): 150, 2021 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-34837964

RESUMO

BACKGROUND: Alzheimer's disease (AD), the most common form of dementia, is caused by the degeneration of the central nervous system (CNS). A previous study reported that signal transducer and activator of transcription 3 (STAT3) is activated during AD development; nonetheless, the related mechanism remains unknown. Thus, this study used a cell model to explore whether and how the protein inhibitor of activated STAT3 (PIAS3) is involved in AD development. METHODS: Cerebrospinal fluid (CSF) specimens of 30 patients with AD and 10 normal participants were included in this study. SH-SY5Y cells were used to constructed AD model. Relevant indices were then detected and analyzed. RESULTS: The results showed that compared with the control group, PIAS3 expression was substantially decreased in patients with AD and amyloid beta (Aß)-treated SH-SY5Y cells. PIAS3 overexpression was able to reverse the detrimental effects of Aß treatment on cell survival and growth. Further, it could also ameliorate apoptosis and oxidative stress in Aß-treated SH-SY5Y cells. Additionally, PIAS3 was shown to reduce the activated form of STAT3 and increase the activity of the downstream Nestin/nuclear factor erythroid 2-related factor/heme oxygenase-1 pathway. CONCLUSIONS: STAT3 reactivation by colivelin treatment negated the influence of PIAS3 on the survival, growth, apoptosis, and oxidative stress of Aß-treated SH-SY5Y cells.


Assuntos
Doença de Alzheimer , Chaperonas Moleculares , Proteínas Inibidoras de STAT Ativados , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/farmacologia , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Heme Oxigenase-1/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Pessoa de Meia-Idade , Modelos Biológicos , Chaperonas Moleculares/líquido cefalorraquidiano , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Fator 2 Relacionado a NF-E2/genética , Nestina/genética , Proteínas Inibidoras de STAT Ativados/líquido cefalorraquidiano , Proteínas Inibidoras de STAT Ativados/genética , Proteínas Inibidoras de STAT Ativados/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Adulto Jovem
13.
Genes Cells ; 25(6): 364-374, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32160394

RESUMO

Microglial inflammation is identified as a key process associated with Parkinson's disease (PD) pathogenesis. Our previous study showed that miR-29c-3p (miR-29c) exhibited anti-inflammatory properties in PD animal and neuronal models. However, the specific role and regulatory mechanism of miR-29c played in microglia are still unclear. In this study, lipopolysaccharide (LPS)-stimulated BV-2 cells were used to establish a cellular model of microglial activation for investigating PD. The results showed a decreased expression of miR-29c in LPS-induced BV-2 cells. Over-expression of miR-29c suppressed LPS-triggered Iba-1 increment, pro-inflammatory cytokine release, and NF-кB and TXNIP/NLRP3 inflammasome activation. Silence of miR-29c induced similar effects with LPS on microglial inflammation. In addition, we found that NFAT5 was negatively correlated with miR-29c. Knockdown of NFAT5 blocked the aggravated inflammation in microglia treated by miR-29c inhibitor. Thus, these findings suggest that miR-29c modulates NLRP3 inflammasome to impair microglial inflammatory responses by targeting NFAT5, which represents a promising therapeutic target for PD.


Assuntos
Inflamassomos/metabolismo , MicroRNAs/metabolismo , Microglia/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Doença de Parkinson/metabolismo , Fatores de Transcrição/metabolismo , Regiões 3' não Traduzidas , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Linhagem Celular , Citocinas/metabolismo , Técnicas de Silenciamento de Genes , Inflamassomos/efeitos dos fármacos , Inflamassomos/genética , Inflamação/genética , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , MicroRNAs/genética , Proteínas dos Microfilamentos/metabolismo , Microglia/efeitos dos fármacos , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Doença de Parkinson/genética , Doença de Parkinson/patologia , Fatores de Transcrição/genética , Regulação para Cima
14.
Org Biomol Chem ; 19(39): 8492-8496, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34549771

RESUMO

Highly enantioselective formal [3 + 2] cycloaddition of N-2,2,2-trifluoroethylisatin ketimines with aurone derivatives of low reactivity using chiral dinuclear zinc catalysts has been developed via a Brønsted base and Lewis acid cooperative activation model. These transformations involving a domino Michael/Mannich reaction sequence led to efficient construction of a range of chiral spiro[benzofuran-pyrrolidine] scaffolds bearing three biologically relevant heterocyclic moieties and two adjacent spiro quaternary stereocenters in high yields (up to 95%) and with good enantioselectivities (up to 99% ee).

15.
Parasitol Res ; 120(8): 2827-2837, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34272998

RESUMO

Currently, conjugation of artemisinin-derived dimers, trimers, and tetramers is a viable strategy for developing new effective antimalarial candidates. Furthermore, nanotechnology is an effective means to achieve intravenous administration of hydrophobic drugs. In this paper, an ester-linked dihydroartemisinin trimer (DHA3) was synthesized and further prepared as self-assembled nanoparticles (DHA3NPs) by a one-step nanoprecipitation method. The pharmacokinetics and antimalarial pharmacodynamics of DHA3NPs were studied in rats and mice infected with Plasmodium yoelii BY265 (PyBY265). DHA3NPs had a regular spherical shape with a uniform size distribution of 140.27 ± 3.59 nm, entrapment efficiency (EE) of 99.63 ± 0.17%, and drug loading efficiency (DL) of 79.62 ± 0.11%. The in vitro release characterization revealed that DHA3NPs were easily hydrolysed into DHA in an esterase environment. The pharmacokinetics study demonstrated that the area under the concentration-time curve (AUC0-t) of DHA in DHA3NPs group was 2070.52 ± 578.76 h×ng×mL-1, which was higher than that of DHA and artesunate (AS) control groups (AUC0-t values of 724.18 ± 94.32 and 448.40 ± 94.45 h×ng×mL-1, respectively) (P < 0.05). The antimalarial pharmacodynamics in vivo suggested that DHA3NPS (ED90 7.82 ± 1.16 µmol×(kg×day)-1) had a superior antimalarial effect compared with that of control groups (ED90 values of 14.68 ± 0.98 (DHA) and 14.34 ± 1.96 (AS) µmol×(kg×day)-1) (P < 0.05). In addition, DHA3NPS reduced the recurrence ratio and improved the cure ratio and survival time. In summary, DHA3NPs exhibited promising pharmacokinetic characteristics and antimalarial pharmacodynamics in vivo.


Assuntos
Antimaláricos , Artemisininas , Malária/tratamento farmacológico , Nanopartículas , Animais , Antimaláricos/farmacocinética , Antimaláricos/farmacologia , Artemisininas/farmacocinética , Artemisininas/farmacologia , Artesunato , Camundongos , Plasmodium yoelii , Ratos
16.
Drug Dev Ind Pharm ; 47(3): 454-464, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33646854

RESUMO

OBJECTIVE: The choline derivative (CD) and polyethylene-glycol (PEG) dually modified artemether (ARM) nanostructured lipid carriers (CD-PEG-ARM-NLC) have been designed to prolong the circulation of ARM in blood, as well as to develop targeting for new permeability pathways (NPPs) and erythrocyte choline carriers (ECCs) that are expressed on the Plasmodium-infected erythrocyte membrane. SIGNIFICANCE: The CD-PEG-ARM-NLC constructed in this study was found to be able to target endoerythrocytic Plasmodium by increasing the drug concentration and residence time in the infected erythrocytic microenvironment and minimizing toxicity and side effects. METHODS: CD-PEG-ARM-NLC was prepared using high-pressure homogenization followed by physicochemical characterization. The targeting ability of CD-PEG-NLC to infected erythrocytes probed by coumarin-6 was investigated by using fluorescence microscopy imaging. The SYBR Green I assay for parasite nucleic acid was adapted in order to assess the efficacy of inhibition against parasite growth in vitro. The antimalarial activity of ARM-loaded NLCs was evaluated by a Pearson four-day suppressive test in Pyy265BY-bearing mice. RESULTS: In vitro imaging indicated that the intracellular delivery of CD-PEG-ARM-NLC was efficiently taken up by the infected erythrocytes via ECCs and NPPs, which could be inhibited by addition of furosemide (an inhibitor of NPPs) and excessive choline (native substrate of ECCs). Moreover, in vitro and in vivo studies that evaluated antimalarial activity suggested that CD-PEG-ARM-NLC exhibited higher antimalarial activity in comparison to ARM-NLC and PEG-ARM-NLC. CONCLUSION: These findings suggested that choline and PEG dually modified NLC could be promising preparations for the production of hydrophobic antimalarial drugs, particularly for ARM.


Assuntos
Nanoestruturas , Plasmodium , Animais , Artemeter , Colina , Portadores de Fármacos , Eritrócitos , Camundongos , Tamanho da Partícula , Polietilenoglicóis
17.
Parasitology ; 147(1): 58-64, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31556865

RESUMO

It is urgent to develop new antimalarial drugs with good therapeutic effects to address the emergence of drug resistance. Here, the artelinic acid-choline derivative (AD) was synthesized by dehydration reaction and esterification reaction, aimed to avoid the emergence of drug resistance by synergistic effect of artemisinins and choline derivative, which could compete with choline for rate-limiting enzymes in the phosphatidylcholine (PC) biosynthetic pathway. AD was formulated into liposomes (ADLs) by the thin-film hydration method. Efficacy of ADLs was evaluated by Peters 4-day suppression test. The suppression percentage against Plasmodium yoelii BY265 (PyBY265) in ADLs group was higher than those of positive control groups (dihydroartemisinin liposomes, P < 0.05) and other control groups (P ⩽ 0.05) at the doses of 4.4, 8.8, 17.6 µmol (kg·d)-1, respectively. The negative conversion fraction, recrudescence fraction and survival fraction of ADLs group were superior to other control groups. Pharmacokinetics in rats after intravenous injection suggested that ADLs exhibited higher exposure levels (indexed by area under concentration-time curve) than that of AD solution, artelinic acid liposomes or artelinic acid solution (P < 0.01). Taken together, ADLs exhibited promising antimalarial efficacy and pharmacokinetic characteristics.


Assuntos
Artemisininas/química , Colina/química , Lipossomos/farmacologia , Lipossomos/farmacocinética , Plasmodium yoelii/efeitos dos fármacos , Animais , Antimaláricos/farmacocinética , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Artemisininas/farmacocinética , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Colina/farmacocinética , Colina/farmacologia , Colina/uso terapêutico , Lipossomos/química , Lipossomos/uso terapêutico , Malária/tratamento farmacológico , Camundongos , Camundongos Endogâmicos ICR , Ratos , Ratos Sprague-Dawley
18.
Cell Mol Biol (Noisy-le-grand) ; 66(2): 146-152, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415942

RESUMO

This research aimed to investigate the effect of miR-124 on the PI3K/Akt signaling pathway in refractory epilepsy rats. Ten healthy SD rats were selected as a control group, thirty-six successfully established model rats were randomly divided into the model group, mir-124-agomir, mir-124-antagomir, mir-124-agomir+ LY294002 group (combined group), with 9 rats in each group. PI3K or (and) Akt expressions were intervened respectively. The changes in attack latency and cognitive function were observed, and the correlation among miR-124, PI3K, Akt, and attack latency was analyzed. Up-regulation of the level of miR-124 could increase the seizure interval of rats (P< 0.05), improve the cognitive function of rats (P< 0.05), and promote the expression of PI3K, AKT. The level of miR-124, PI3K, Akt was positively correlated with the latent time of seizures in rats, and the level of miR-124 was positively correlated with the level of PI3K, Akt (P< 0.05). In conclusion, miR-124 can play a protective role in temporal lobe epilepsy by promoting PI3K/Akt signaling pathway, including the protection of cognitive function, which may be a potential target for clinical treatment of intractable epilepsy in the future.


Assuntos
Epilepsia Resistente a Medicamentos/patologia , MicroRNAs/metabolismo , Transdução de Sinais/genética , Animais , Antagomirs/metabolismo , Antagomirs/uso terapêutico , Modelos Animais de Doenças , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Epilepsia Resistente a Medicamentos/metabolismo , Hipocampo/metabolismo , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/química , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley
19.
Clin Exp Pharmacol Physiol ; 47(3): 372-382, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31732967

RESUMO

MicroRNAs (miRNAs) have been shown to have complicated implications in the pathogenesis of Parkinson's disease (PD). However, the role of miR-29c and the underlying mechanism in the development of PD remain not well understood. In this work, the MPTP-treated mice or MPP+ -intoxicated SH-SY5Y cells were established as an in vivo or in vitro PD model. Then the specific agomir of miR-29c was employed to examine its biological function on PD progress. We found that miR-29c was down-expressed but SP1 was high-expressed in substantia nigra pars compacta (SNpc) of MPTP-induced PD mice. Overexpression of miR-29c attenuated dopaminergic neuron loss and α-synuclein accumulation in SNpc of PD mice. Furthermore, the increments of pro-inflammatory cytokines (TNF-α, IL-1ß and IL-6) and TUNEL-positive apoptotic cells in MPTP-treated mice were ameliorated by miR-29c. Similarly, in SH-SY5Y cell models of PD, we also found that miR-29c inhibited inflammatory cytokine production, reduced apoptotic rate and suppressed pro-apoptotic regulator activity. In addition, the increased expression of SP1 in PD models was found to be inhibited by miR-29c. Luciferase reporter assay confirmed that SP1 was complementary with miR-29c. Knockdown of SP1 with siRNA restored α-synuclein accumulation, inflammation and apoptosis in MPP+ -induced SH-SY5Y cells. Collectively, this current work presents that miR-29c may directly target SP1 to protect against the neuroinflammatory and apoptotic responses in PD, providing a potential biomarker for PD diagnosis and treatment.


Assuntos
Apoptose/fisiologia , MicroRNAs/biossíntese , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/prevenção & controle , Fator de Transcrição Sp1/biossíntese , Animais , Linhagem Celular Tumoral , Humanos , Inflamação/metabolismo , Inflamação/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transtornos Parkinsonianos/patologia , Distribuição Aleatória , Fator de Transcrição Sp1/antagonistas & inibidores
20.
Xenobiotica ; 50(11): 1323-1331, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32369406

RESUMO

The compound 20(S),25-epoxydammarane-3ß,12ß,24α-triol (24-hydroxy-panaxadiol or 24-OH-PD), isolated from the red Panax ginseng CA Meyer possesses anticancer activity. Our aim was to study the pharmacokinetic characteristics of 24-OH-PD, which is essential for pre-clinical research during the development of new drugs. In this study, a simple and sensitive ultra-performance liquid chromatography-mass spectrometry (LC-MS/MS) method was established and used for studying the pharmacokinetics, in vitro protein binding, tissue distribution, and elimination profiles of 24-OH-PD in rats. 24-OH-PD was characterized by linear pharmacokinetics in the dose range of 2.5-10 mg/kg and had relatively longer half-life (4.82-5.45 h) than the other ginsenosides. It had a wide tissue distribution profile in rats and was primarily distributed in the lung. Within 96 h of intravenous administration, 13.84% of 24-OH-PD was excreted out via feces and 0.02% via urine in its unchanged form. In conclusion, a simple LC-MS/MS method with high sensitivity and selectivity was established for the quantification of 24-OH-PD.


Assuntos
Antineoplásicos/farmacocinética , Medicamentos de Ervas Chinesas/farmacocinética , Animais , Antineoplásicos/metabolismo , Líquidos Corporais , Medicamentos de Ervas Chinesas/metabolismo , Panax , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
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