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2.
Front Microbiol ; 15: 1401436, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38751721

RESUMO

Broad bean paste is a popular condiment in Asian countries. Leaves of Vitex negundo Linn. were used extensively in China during the koji-making of broad bean paste. Spreading V. negundo leaves on raw broad beans during fermentation was able to facilitate the rapid growth of fungi to form mature koji. We isolated two strains of fungi from mature koji, and four strains of bacteria from the rotten broad beans resulting from a failed attempt. According to microbial activity assays, two polymethoxylated flavones, 5-hydroxy-3,6,7,8,3',4'-hexamethoxy flavone (HJ-1) and 5,4'-dihydroxy-3,6,7,8,3'-pentamethoxy flavone (HJ-2) were isolated from V. negundo leaves, and the fungal growth promotion and inhibition of bacterial growth of these two compounds were found to improve the production of broad bean koji. This study reveals the compounds present in V. negundo leaves with bioactivity against important microbes in koji manufacture, and provides a theoretical basis for the application of V. negundo in broad bean paste production.

3.
Appl Microbiol Biotechnol ; 108(1): 326, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717487

RESUMO

Aspartyl dipeptidase (dipeptidase E) can hydrolyze Asp-X dipeptides (where X is any amino acid), and the enzyme plays a key role in the degradation of peptides as nutrient sources. Dipeptidase E remains uncharacterized in Streptomyces. Orf2 from Streptomyces sp. 139 is located in the exopolysaccharide biosynthesis gene cluster, which may be a novel dipeptidase E with "S134-H170-D198" catalytic triad by sequence and structure comparison. Herein, recombinant Orf2 was expressed in E. coli and characterized dipeptidase E activity using the Asp-ρNA substrate. The optimal pH and temperature for Orf2 are 7.5 and 40 ℃; Vmax and Km of Orf2 are 0.0787 mM·min-1 and 1.709 mM, respectively. Orf2 exhibits significant degradation activities to Asp-Gly-Gly, Asp-Leu, Asp-His, and isoAsp-Leu and minimal activities to Asp-Pro and Asp-Ala. Orf2 contains a Ser-His-Asp catalytic triad characterized by point mutation. In addition, the Asp147 residue of Orf2 is also proven to be critical for the enzyme's activity through molecular docking and point mutation. Transcriptome analysis reveals the upregulation of genes associated with ribosomes, amino acid biosynthesis, and aminoacyl-tRNA biosynthesis in the orf2 mutant strain. Compared with the orf2 mutant strain and WT, the yield of crude polysaccharide does not change significantly. However, crude polysaccharides from the orf2 mutant strain exhibit a wider range of molecular weight distribution. The results indicate that the Orf2 links nutrient stress to secondary metabolism as a novel dipeptidase E. KEY POINTS: • A novel dipeptidase E with a Ser-His-Asp catalytic triad was characterized from Streptomyces sp. 139. • Orf2 was involved in peptide metabolism both in vitro and in vivo. • Orf2 linked nutrient stress to mycelia formation and secondary metabolism in Streptomyces.


Assuntos
Escherichia coli , Streptomyces , Streptomyces/genética , Streptomyces/enzimologia , Escherichia coli/genética , Escherichia coli/metabolismo , Especificidade por Substrato , Dipeptidases/metabolismo , Dipeptidases/genética , Dipeptidases/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Simulação de Acoplamento Molecular , Família Multigênica , Concentração de Íons de Hidrogênio , Dipeptídeos/metabolismo , Temperatura , Cinética
4.
Ultrason Sonochem ; 105: 106872, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599128

RESUMO

The present study aimed to investigate the potential of ultrasonic treatment during fermentation for enhancing the quality of fortified wines with varying time and power settings. Chemical analysis and sensory evaluation were conducted to assess the impact of ultrasonic treatment on wine quality. Results showed that ultrasonic treatment could increase total anthocyanin and total phenol content, reduce anthocyanin degradation rate, and improve color stability. Moreover, ethyl carbamate content was lower in the ultrasonic group after aging compared to non-ultrasonic group. A combination of 200 W for 20 min resulted in higher sensory scores and more coordinated taste, while a combination of 400 W for 40 min produced higher levels of volatile compounds (21860.12 µg/L) leading to a richer and more elegant aroma. Therefore, ultrasound can be used as a potential technology to improve the quality of wine.


Assuntos
Antocianinas , Fermentação , Vinho , Vinho/análise , Antocianinas/análise , Paladar , Qualidade dos Alimentos , Ondas Ultrassônicas , Cor , Alimentos Fortificados/análise , Fenóis/análise
5.
Pharmacol Res ; 203: 107168, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38583689

RESUMO

Parkinson's disease (PD) is a common neurodegenerative disease characterized by progressive loss of dopaminergic neurons in the substantia nigra and the aggregation of alpha-synuclein (α-syn). The central nervous system (CNS) has previously been considered as an immune-privileged area. However, studies have shown that the immune responses are involved in PD. The major histocompatibility complex (MHC) presents antigens from antigen-presenting cells (APCs) to T lymphocytes, immune responses will be induced. MHCs are expressed in microglia, astrocytes, and dopaminergic neurons. Single nucleotide polymorphisms in MHC are related to the risk of PD. The aggregated α-syn triggers the expression of MHCs by activating glia cells. CD4+ and CD8+ T lymphocytes responses and microglia activation are detected in brains of PD patients. In addiction immune responses further increase blood-brain barrier (BBB) permeability and T cell infiltration in PD. Thus, MHCs are involved in PD through participating in immune and inflammatory responses.


Assuntos
Complexo Principal de Histocompatibilidade , Doença de Parkinson , Humanos , Doença de Parkinson/imunologia , Doença de Parkinson/genética , Animais , Complexo Principal de Histocompatibilidade/imunologia , alfa-Sinucleína/imunologia , alfa-Sinucleína/metabolismo , Barreira Hematoencefálica/imunologia , Barreira Hematoencefálica/metabolismo , Microglia/imunologia , Microglia/metabolismo
6.
Plants (Basel) ; 13(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38674483

RESUMO

Olibanum, a golden oleo-gum resin from species in the Boswellia genus (Burseraceae family), is a famous traditional herbal medicine widely used around the world. Previous phytochemical studies mainly focused on the non-polar fractions of olibanum. In this study, nine novel diterpenoids, boswellianols A-I (1-9), and three known compounds were isolated from the polar methanolic fraction of the oleo-gum resin of Boswellia carterii. Their structures were determined through comprehensive spectroscopic analysis as well as experimental and calculated electronic circular dichroism (ECD) data comparison. Compound 1 is a novel diterpenoid possessing an undescribed prenylmaaliane-type skeleton with a 6/6/3 tricyclic system. Compounds 2-4 were unusual prenylaromadendrane-type diterpenoids, and compounds 5-9 were new highly oxidized cembrane-type diterpenoids. Compounds 1 and 5 showed significant transforming growth factor ß (TGF-ß) inhibitory activity via inhibiting the TGF-ß-induced phosphorylation of Smad3 and the expression of fibronectin and N-cadherin (the biomarker of the epithelial-mesenchymal transition) in a dose-dependent manner in LX-2 human hepatic stellate cells, indicating that compounds 1 and 5 should be potential anti-fibrosis agents. These findings give a new insight into the chemical constituents of the polar fraction of olibanum and their inhibitory activities on the TGF-ß/Smad signaling pathway.

8.
Medicine (Baltimore) ; 103(13): e37551, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38552066

RESUMO

This study aimed to investigate the feasibility, indications, and benefits of transvaginal natural orifice transluminal endoscopic surgery (v-NOTES) hysterectomy for nonmalignant gynecological diseases. The clinical data, including the baseline information and surgical conditions of 81 patients who underwent v-NOTES hysterectomy for nonmalignant gynecological diseases in a tertiary university hospital from October 2018 to August 2022, were retrospectively analyzed and compared with the total laparoscopic hysterectomy group (200 cases) and the transumbilical laparoendoscopic Single Site Surgery group (150 cases). In comparison with the other 2 groups, the highest proportion of patients in the v-NOTES group had cervical intraepithelial neoplasia. Accordingly, mean preoperative uterine volume measured by sonography was significantly smaller in the v-notes group. In the v-NOTES group, the mean number of vaginal deliveries and age were significantly higher, while the mean number of previous abdominal surgeries was lower compared to the other 2 groups. The V-NOTES group had a shorter operation time, shorter postoperative urinary catheter insertion time, earlier intestinal recovery days, shorter hospital stay, and lower visual analogue scale scores after surgery, and the differences were statistically significant. When indicated appropriately, v-NOTES hysterectomy can be a feasible and advantageous surgical modality. In particular, in comparison to the laparoendoscopic Single Site Surgery and total laparoscopic hysterectomy groups, the v-NOTES group had advantages in postoperative recovery and had more aesthetic surgical results.


Assuntos
Laparoscopia , Cirurgia Endoscópica por Orifício Natural , Feminino , Humanos , Histerectomia Vaginal/métodos , Estudos Transversais , Estudos Retrospectivos , Histerectomia/métodos , Cirurgia Endoscópica por Orifício Natural/métodos , Laparoscopia/métodos
9.
Phytochemistry ; 220: 114018, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342288

RESUMO

Steroidal alkaloids are the main bioactive components of the bulbs of Fritillaria, which have been used as traditional Chinese medicine, known as "Beimu", for the treatment of cough for thousands of years in China. Cough and dyspnea are the most common symptoms observed in patients with pulmonary fibrosis. However, the antifibrotic activity of steroidal alkaloids has not been reported yet. In this study, two previously unreported cevanine-type steroidal alkaloids (1 and 2), four previously undescribed cevanine-type alkaloid glycosides (3-6), and 19 known steroidal alkaloids (7-25) were isolated from the bulbs of Fritillaria unibracteata var. wabuensis. The structures of these compounds were elucidated by comprehensive HRESIMS and NMR spectroscopic data analysis, as well as DP4+ NMR calculations. The biological evaluation showed that compounds 2, 7-10, 14, 15, and 17 downregulated fibrotic markers induced by transforming growth factor-ß (TGF-ß) in MRC-5 cells. Moreover, compounds 14 and 17 dose dependently inhibited TGF-ß-induced epithelial-mesenchymal transition in A549 cells, alleviated TGF-ß-induced migration and proliferation of fibroblasts, and decreased the expression of fibrotic markers, fibronectin, and N-cadherin in TGF-ß-induced MRC-5 cells. The research showed the potential of cevanine-type alkaloids as a class of natural antifibrotic agents.


Assuntos
Alcaloides , Fritillaria , Humanos , Fritillaria/química , Alcaloides/química , Raízes de Plantas/química , Tosse , Esteroides/química , Fator de Crescimento Transformador beta/análise
10.
Cell Death Discov ; 10(1): 93, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388451

RESUMO

Parkinson's disease (PD) is characterized by the formation of Lewy body in dopaminergic neurons in the substantia nigra pars compacta (SNpc). Alpha-synuclein (α-syn) is a major component of Lewy body. Autophagy eliminates damaged organelles and abnormal aggregated proteins. Thioredoxin-1 (Trx-1) is a redox regulating protein and plays roles in protecting dopaminergic neurons against neurotoxicity induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). However, the relationship between Trx-1 and α-syn in PD is still unknown. In the present study, the movement disorder and dopaminergic neurotoxicity in MPTP-treated mice were improved by Trx-1 overexpression and were aggravated by Trx-1 knockdown in the SNpc in mice. The expression of α-syn was increased in the SNpc of MPTP-treated mice, which was inhibited by Trx-1 overexpression and was exacerbated in Trx-1 knockdown mice. Autophagosomes was increased under electron microscope after MPTP treatment, which were recovered in Trx-1 overexpressing mice and were further increased in Trx-1 knockdown in the SNpc in mice. The expressions of phosphatase and tensin homolog deleted on chromosome ten (PTEN)-induced putative kinase 1 (PINK1), Parkin, LC3 II and p62 were increased by MPTP, which were blocked in Trx-1 overexpressing mice and were further increased in Trx-1 knockdown mice. Cathepsin D was decreased by MPTP, which was restored in Trx-1 overexpressing mice and was further decreased in Trx-1 knockdown mice. The mRFP-GFP-LC3 green fluorescent dots were increased by 1-methyl-4-phenylpyridinium (MPP+) and further increased in Trx-1 siRNA transfected PC12 cells, while mRFP-GFP-LC3 red fluorescent dots were increased in Trx-1 overexpressing cells. These results indicate that Trx-1 may eliminate α-syn in PD mice through potentiating autophagy-lysosome pathway.

11.
Mol Biol Rep ; 51(1): 248, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300413

RESUMO

Programmed cell death is a major life activity of both normal development and disease. Necroptosis is early recognized as a caspase-independent form of programmed cell death followed obviously inflammation. Apoptosis is a gradually recognized mode of cell death that is characterized by a special morphological changes and unique caspase-dependent biological process. Ferroptosis, pyroptosis and autophagy are recently identified non-apoptotic regulated cell death that each has its own characteristics. The transient receptor potential vanilloid 4 (TRPV4) is a kind of nonselective calcium-permeable cation channel, which is received more and more attention in biology studies. It is widely expressed in human tissues and mainly located on the membrane of cells. Several researchers have identified that the influx Ca2+ from TRPV4 acts as a key role in the loss of cells by apoptosis, ferroptosis, necroptosis, pyroptosis and autophagy via mediating endoplasmic reticulum (ER) stress, oxidative stress and inflammation. This effect is bad for the normal function of organs on the one hand, on the other hand, it is benefit for anticancer activities. In this review, we will summarize the current discovery on the role and impact of TRPV4 in these programmed cell death pathological mechanisms to provide a new prospect of gene therapeutic target of related diseases.


Assuntos
Antineoplásicos , Canais de Cátion TRPV , Humanos , Canais de Cátion TRPV/genética , Apoptose , Morte Celular , Caspases , Canais de Cálcio , Inflamação
12.
Acta Pharm Sin B ; 14(2): 821-835, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38322329

RESUMO

Radiotherapy (RT) can potentially induce systemic immune responses by initiating immunogenic cell death (ICD) of tumor cells. However, RT-induced antitumor immunologic responses are sporadic and insufficient against cancer metastases. Herein, we construct multifunctional self-sufficient nanoparticles (MARS) with dual-enzyme activity (GOx and peroxidase-like) to trigger radical storms and activate the cascade-amplified systemic immune responses to suppress both local tumors and metastatic relapse. In addition to limiting the Warburg effect to actualize starvation therapy, MARS catalyzes glucose to produce hydrogen peroxide (H2O2), which is then used in the Cu+-mediated Fenton-like reaction and RT sensitization. RT and chemodynamic therapy produce reactive oxygen species in the form of radical storms, which have a robust ICD impact on mobilizing the immune system. Thus, when MARS is combined with RT, potent systemic antitumor immunity can be generated by activating antigen-presenting cells, promoting dendritic cells maturation, increasing the infiltration of cytotoxic T lymphocytes, and reprogramming the immunosuppressive tumor microenvironment. Furthermore, the synergistic therapy of RT and MARS effectively suppresses local tumor growth, increases mouse longevity, and results in a 90% reduction in lung metastasis and postoperative recurrence. Overall, we provide a viable approach to treating cancer by inducing radical storms and activating cascade-amplified systemic immunity.

13.
Bioorg Chem ; 144: 107111, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218068

RESUMO

To mine fascinating molecules from the rhizomes of Atractylodes chinensis, the known molecular formula of atrachinenin A was used as a bait to search LC-HRMS data in different subfractions. Sixteen new meroterpenoids, atrachinenins D-S (1-16) including three unprecedented carbon skeletons (1-5) and eleven new oxygen-bridged hybrids (6-16) were obtained by the targeted isolation. Their structures and absolute configurations were elucidated by the spectroscopic data and electronic circular dichroism (ECD) calculations. The isolated compounds were evaluated for their inhibitory activity of NO production and compounds 1, 4, 8, and 13 showed moderate anti-inflammatory activity. The proposed biosynthetic pathways of 1-5 were also discussed.


Assuntos
Atractylodes , Atractylodes/química , Hidroquinonas , Anti-Inflamatórios , Dicroísmo Circular , Estrutura Molecular
14.
Int J Mol Sci ; 24(23)2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38069376

RESUMO

Rice (Oryza sativa L.) is thought to have been domesticated many times independently in China and India, and many modern cultivars are available. All rice tissues are rich in specialized metabolites (SPMs). To date, a total of 181 terpenoids, 199 phenolics, 41 alkaloids, and 26 other types of compounds have been detected in rice. Some volatile sesquiterpenoids released by rice are known to attract the natural enemies of rice herbivores, and play an indirect role in defense. Momilactone, phytocassane, and oryzalic acid are the most common diterpenoids found in rice, and are found at all growth stages. Indolamides, including serotonin, tryptamine, and N-benzoylserotonin, are the main rice alkaloids. The SPMs mainly exhibit defense functions with direct roles in resisting herbivory and pathogenic infections. In addition, phenolics are also important in indirect defense, and enhance wax deposition in leaves and promote the lignification of stems. Meanwhile, rice SPMs also have allelopathic effects and are crucial in the regulation of the relationships between different plants or between plants and microorganisms. In this study, we reviewed the various structures and functions of rice SPMs. This paper will provide useful information and methodological resources to inform the improvement of rice resistance and the promotion of the rice industry.


Assuntos
Alcaloides , Diterpenos , Oryza , Oryza/metabolismo , Terpenos/metabolismo , Diterpenos/metabolismo , Plantas/metabolismo , Alcaloides/metabolismo , Herbivoria
15.
ACS Appl Mater Interfaces ; 15(46): 53228-53241, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37943281

RESUMO

Nonapoptotic ferroptosis is a promising cancer treatment which offers a solution to the multidrug resistance of conventional apoptosis-induced programmed cancer cell death therapies. Reducing intracellular glutathione (GSH) is essential for inducing excess ROS and has been considered a crucial process to trigger ferroptosis. However, treatments reducing GSH alone have not produced satisfactory effects due to their restricted target. In this regard, FeCDs (Fe3+-modified l-histidine -sourced carbon dots) with dual GSH-consumption capabilities were constructed to engineer ferroptosis by self-amplifying intratumoral oxidative stress. Carbon dots have the ability to consume GSH, and the introduction of Fe3+ can amplify the GSH-consuming ability of CDs, reacting with excess H2O2 in the tumor microenvironment to generate highly oxidized •OH. This is a novel strategy through synergistic self-amplification therapy combining Fe3+ and CDs with GSH-consuming activity. The acid-triggered degradation material (FeCDs@PAE-PEG) was prepared by encapsulating FeCDs in an oil-in-water manner. Compared with other ferroptosis-triggering nanoparticles, the established FeCDs@PAE-PEG is targeted and significantly enhances the consumption efficiency of GSH and accumulation of excess iron without the involvement of infrared light and ultrasound. This synergistic strategy exhibits excellent ferroptosis-inducing ability and antitumor efficacy both in vitro and in vivo and offers great potential for clinical translation of ferroptosis.


Assuntos
Ferroptose , Neoplasias , Humanos , Peróxido de Hidrogênio , Apoptose , Carbono , Glutationa , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Espécies Reativas de Oxigênio , Microambiente Tumoral
16.
Sci Bull (Beijing) ; 68(20): 2418-2433, 2023 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-37739838

RESUMO

Mountain and polar glaciers cover 10% of the Earth's surface and are typically extreme environments that challenge life of all forms. Viruses are abundant and active in supraglacial ecosystems and play a crucial role in controlling the supraglacial microbial communities. However, our understanding of virus ecology on glacier surfaces and their potential impacts on downstream ecosystems remains limited. Here, we present the supraglacial virus genome (SgVG) catalog, a 15-fold expanded genomic inventory of 10,840 DNA-virus species from 38 mountain and polar glaciers, spanning habitats such as snow, ice, meltwater, and cryoconite. Supraglacial DNA-viruses were highly specific compared to viruses in other ecosystems yet exhibited low public health risks. Supraglacial viral communities were primarily constrained by habitat, with cryoconite displaying the highest viral activity levels. We observed a prevalence of lytic viruses in all habitats, especially in cryoconite, but a high level of lysogenic viruses in snow and ice. Additionally, we found that supraglacial viruses could be linked to ∼83% of obtained prokaryotic phyla/classes and possessed the genetic potential to promote metabolism and increase cold adaptation, cell mobility, and phenolic carbon use of hosts in hostile environmental conditions using diverse auxiliary metabolic genes. Our results provide the first systematic characterization of the diversity, function, and public health risks evaluation of mountain and polar supraglacial DNA viruses. This understanding of glacial viruses is crucial for function assessments and ecological modeling of glacier ecosystems, especially for the Tibetan Plateau's Mountain glaciers, which support ∼20% of the human populations on Earth.


Assuntos
Gelo , Microbiota , Humanos , Vírus de DNA/genética , DNA
17.
J Pharm Biomed Anal ; 235: 115603, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37542829

RESUMO

Cordyceps sinensis is a precious medicinal food which has been successfully cultivated indoors. It remains to be investigated for a simultaneous comparison on aqueous components of natural and cultivated samples. Herein, an approach of quantitative nuclear magnetic resonance (qNMR) analysis combined with global spectral deconvolution (GSD) was established for simultaneous quantification of 26 aqueous components in C. sinensis. Processed by GSD, the distorted baselines of 1H NMR spectra were greatly improved, and overlapped signals were also well separated so as to achieve accurate identification and quantitation of components in C. sinensis. Method validation by UHPLC-QTOF-MS and TOF-SIMS analysis revealed that qNMR combined with GSD is a reliable approach for simultaneous quantification of multiple components including characteristic markers of glutamine, GABA and trehalose in authentic and fake C. sinensis. The well-established qNMR approach can be used for quality assessment of natural and cultivated C. sinensis as well as differentiation from fake ones.


Assuntos
Cordyceps , Cordyceps/química , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Imageamento por Ressonância Magnética , Água
18.
Fitoterapia ; 169: 105604, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37423500

RESUMO

Five undescribed sesquiterpenoid dimers, aucklandiolides A-E (1-5), one new sesquiterpenoid glycoside, ß-cyclocostunolide-15-ß-D-glucopyranoside (6), and seventeen known analogues (7-23) were isolated from the roots of Aucklandia costus. Their structures were elucidated by comprehensive HRESIMS and NMR spectroscopic data analysis, and their configurations were confirmed by the computational calculations of ECD and NMR chemical shifts. Aucklandiolides A and B are the first examples of dimeric sesquiterpenoids with a unique 6/6/6/5/6/6 ring system originated from a proposed Diels-Alder cycloaddition between two eudesmane sesquiterpenoids. Besides, compounds 9-11, 20, and 22 showed significant inhibition of nitric oxide production in LPS-stimulated RAW 264.7 cells at a concentration of 20 µM.


Assuntos
Saussurea , Sesquiterpenos , Animais , Camundongos , Estrutura Molecular , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Células RAW 264.7 , Óxido Nítrico , Sesquiterpenos/farmacologia , Sesquiterpenos/química
19.
ACS Nano ; 17(12): 11414-11426, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37310989

RESUMO

Redox heterogeneity of tumor cells has become one of the key factors leading to the failure of conventional photodynamic therapy (PDT). Exploration of a distinctive therapeutic strategy addressing heterogeneous predicaments is an appealing yet highly challenging task. Herein, a multiple stimuli-responsive nanoCRISPR (Must-nano) with spatial arrangement peculiarities in nanostructure and intracellular delivery is fabricated to overcome redox heterogeneity at both genetic and phenotypic levels for tumor-specific activatable PDT. Must-nano consists of a redox-sensitive core loading CRISPR/Cas9 targeting hypoxia-inducible factors-1α (HIF-1α) and a rationally designed multiple-responsive shell anchored by chlorin e6 (Ce6). Benefiting from the perfect coordination of structure and function, Must-nano avoids enzyme/photodegradation of the CRISPR/Cas9 system and exerts prolonged circulation, precise tumor recognition, and cascade-responsive performances to surmount tumor extra/intracellular barriers. After internalization into tumor cells, Must-nano could undergo hyaluronidase-triggered self-disassembly with charge reversal and rapid endosomal escape, followed by site-specific release and spatially asynchronous delivery of Ce6 and CRISPR/Cas9 under stimulations of redox signals, which not only improves tumor vulnerability to oxidative stress by complete HIF-1α disruption but also destroys the intrinsic antioxidant mechanism through glutathione depletion, thereby homogenizing redox-heterogeneous cells into oxidative stress-sensitive cell subsets. Under laser irradiation, Must-nano eventually exhibits optimal potency to amplify oxidative damage, effectively inhibiting the growth and hypoxia survival of redox-heterogeneous tumor in vitro and in vivo. Overall, our redox homogenization tactic significantly maximizes PDT efficacy and offers a promising strategy to overcome tumor redox heterogeneity in the development of antitumor therapies.


Assuntos
Nanopartículas , Nanoestruturas , Fotoquimioterapia , Porfirinas , Humanos , Linhagem Celular Tumoral , Porfirinas/farmacologia , Porfirinas/química , Hipóxia/tratamento farmacológico , Oxirredução , Fármacos Fotossensibilizantes/química , Nanopartículas/química
20.
Environ Int ; 178: 108038, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37343327

RESUMO

Acetamiprid is poisonous to mammals due to severe acetamiprid-induced oxidative stress that could cause mitochondrial dysfunctions, lipid and protein oxidation, inflammation, apoptosis, and DNA damage. Evidence has accumulated for the role of oxidative stress in changing structures and functions of transfer RNAs (tRNAs) by inducing tRNA cleavage, reprogramming tRNA modifications and impairing aminoacyl-tRNA synthetase editing sites. However, the impact of acetamiprid-induced oxidative stress on tRNA is still unknown. Here, we investigated the effects of acetamiprid on cell viability, reactive oxygen species (ROS) levels, DNA damage, cellular oxidized nucleotide concentrations, and oxidative damage to tRNA in HepG2 cells and LO2 cells. Acetamiprid can cause the significant increment of ROS and DNA oxidative damage. In this study, an integrated approach was established to simultaneously study the network of oxidized nucleotides and explore the tRNA oxidative damage after acetamiprid exposure. A simple and high-throughput liquid chromatography with tandem mass spectrometry (LC-MS/MS) method coupled with (trimethylsilyl)diazomethane (TMSD) derivatization was successfully developed to quantify 12 cellular oxidized nucleotides that cannot be detected using traditional detection methods because of the huge interferences from naturally abundant nucleotides. Meanwhile, the accumulation rate and the locating sites of 8-oxo-2, 7-dihydro-guanine (8-oxo-G) in tRNA were inspected using the established N-(tert-Butyldimethylsilyl)-N-methyl-trifluoroacetamide (MTBSTFA) labeling-based tRNA profiling method. After acetamiprid treatment, the increment of oxidized nucleoside triphosphates is smaller than that of their corresponding mono- and diphosphates, as well as the dephosphorylated nucleosides, on account of the existence of sanitization enzymes. Several tRNA fragments, CUC[m1A]Gp, CACGp, [Cm]C[m2G]p, and DDGp, are significantly downregulated in acetamiprid-treated HepG2 cells, while only [Cm]C[m2G]p in acetamiprid-treated LO2 cells. According to the profiling results, the significantly changed fragment CUC[m1A]Gp might be caused by the oxidation of guanine (G) to form 8-oxo-G at position 15 in human tRNAphe([Gm]AA), providing more information about the effect of oxidized nucleobases on tRNA's functions.


Assuntos
Nucleotídeos , Espectrometria de Massas em Tandem , Animais , Humanos , Nucleotídeos/metabolismo , Espécies Reativas de Oxigênio , Cromatografia Líquida , Estresse Oxidativo , RNA de Transferência/metabolismo , Guanina/metabolismo , Mamíferos/metabolismo
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