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1.
EMBO J ; 42(17): e113415, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37485728

RESUMEN

The human ABC transporter ABCC3 (also known as MRP3) transports a wide spectrum of substrates, including endogenous metabolites and exogenous drugs. Accordingly, it participates in multiple physiological processes and is involved in diverse human diseases such as intrahepatic cholestasis of pregnancy, which is caused by the intracellular accumulation of bile acids and estrogens. Here, we report three cryogenic electron microscopy structures of ABCC3: in the apo-form and in complexed forms bound to either the conjugated sex hormones ß-estradiol 17-(ß-D-glucuronide) and dehydroepiandrosterone sulfate. For both hormones, the steroid nuclei that superimpose against each other occupy the hydrophobic center of the transport cavity, whereas the two conjugation groups are separated and fixed by the hydrophilic patches in two transmembrane domains. Structural analysis combined with site-directed mutagenesis and ATPase activity assays revealed that ABCC3 possesses an amphiphilic substrate-binding pocket able to hold either conjugated hormone in an asymmetric pattern. These data build on consensus features of the substrate-binding pocket of MRPs and provide a structural platform for the rational design of inhibitors.


Asunto(s)
Transportadoras de Casetes de Unión a ATP , Estradiol , Humanos , Transportadoras de Casetes de Unión a ATP/genética , Estradiol/farmacología , Estradiol/metabolismo , Mutagénesis Sitio-Dirigida
2.
Proc Natl Acad Sci U S A ; 121(11): e2318320121, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38457518

RESUMEN

Coordinated carbon and nitrogen metabolism is crucial for bacteria living in the fluctuating environments. Intracellular carbon and nitrogen homeostasis is maintained by a sophisticated network, in which the widespread signaling protein PII acts as a major regulatory hub. In cyanobacteria, PII was proposed to regulate the nitrate uptake by an ABC (ATP-binding cassette)-type nitrate transporter NrtABCD, in which the nucleotide-binding domain of NrtC is fused with a C-terminal regulatory domain (CRD). Here, we solved three cryoelectron microscopy structures of NrtBCD, bound to nitrate, ATP, and PII, respectively. Structural and biochemical analyses enable us to identify the key residues that form a hydrophobic and a hydrophilic cavity along the substrate translocation channel. The core structure of PII, but not the canonical T-loop, binds to NrtC and stabilizes the CRD, making it visible in the complex structure, narrows the substrate translocation channel in NrtB, and ultimately locks NrtBCD at an inhibited inward-facing conformation. Based on these results and previous reports, we propose a putative transport cycle driven by NrtABCD, which is allosterically inhibited by PII in response to the cellular level of 2-oxoglutarate. Our findings provide a distinct regulatory mechanism of ABC transporter via asymmetrically binding to a signaling protein.


Asunto(s)
Cianobacterias , Transportadores de Nitrato , Nitratos/metabolismo , Proteínas Bacterianas/metabolismo , Regulación Alostérica , Microscopía por Crioelectrón , Cianobacterias/metabolismo , Adenosina Trifosfato/metabolismo , Nitrógeno/metabolismo , Carbono/metabolismo , Proteínas PII Reguladoras del Nitrógeno/genética , Proteínas PII Reguladoras del Nitrógeno/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(14): e2118656119, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35349344

RESUMEN

SignificanceATP8B1 is a P4 ATPase that maintains membrane asymmetry by transporting phospholipids across the cell membrane. Disturbance of lipid asymmetry will lead to the imbalance of the cell membrane and eventually, cell death. Thus, defects in ATP8B1 are usually associated with severe human diseases, such as intrahepatic cholestasis. The present structures of ATP8B1 complexed with its auxiliary noncatalytic partners CDC50A and CDC50B reveal an autoinhibited state of ATP8B1 that could be released upon substrate binding. Moreover, release of this autoinhibition could be facilitated by the bile acids, which are key factors that alter the membrane asymmetry of hepatocytes. This enabled us to figure out a feedback loop of bile acids and lipids across the cell membrane.


Asunto(s)
Adenosina Trifosfatasas , Colestasis Intrahepática , Adenosina Trifosfatasas/metabolismo , Ácidos y Sales Biliares/metabolismo , Membrana Celular/metabolismo , Colestasis Intrahepática/metabolismo , Humanos , Proteínas de Transferencia de Fosfolípidos/metabolismo , Fosfolípidos/metabolismo
4.
J Am Chem Soc ; 146(12): 8206-8215, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38412246

RESUMEN

Spin-crossover (SCO) materials exhibit remarkable potential as bistable switches in molecular devices. However, the spin transition temperatures (Tc) of known compounds are unable to cover the entire ambient temperature spectrum, largely limiting their practical utility. This study reports an exemplary two-dimensional SCO solid solution system, [FeIII(H0.5LCl)2-2x(H0.5LF)2x]·H2O (H0.5LX = 5-X-2-hydroxybenzylidene-hydrazinecarbothioamide, X = F or Cl, x = 0 to 1), in which the adjacent layers are adhered via hydrogen bonding. Notably, the Tc of this system can be fine-tuned across 90 K (227-316 K) in a linear manner by modulating the fraction x of the LF ligand. Elevating x results in strengthened hydrogen bonding between adjacent layers, which leads to enhanced intermolecular interactions between adjacent SCO molecules. Single-crystal diffraction analysis and periodic density functional theory calculations revealed that such a special kind of alteration in interlayer interactions strengthens the FeIIIN2O2S2 ligand field and corresponding SCO energy barrier, consequently resulting in increased Tc. This work provides a new pathway for tuning the Tc of SCO materials through delicate manipulation of molecular interactions, which could expand the application of bistable molecular solids to a much wider temperature regime.

5.
Mol Cancer ; 23(1): 122, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38844984

RESUMEN

Metastasis remains the principal cause of cancer-related lethality despite advancements in cancer treatment. Dysfunctional epigenetic alterations are crucial in the metastatic cascade. Among these, super-enhancers (SEs), emerging as new epigenetic regulators, consist of large clusters of regulatory elements that drive the high-level expression of genes essential for the oncogenic process, upon which cancer cells develop a profound dependency. These SE-driven oncogenes play an important role in regulating various facets of metastasis, including the promotion of tumor proliferation in primary and distal metastatic organs, facilitating cellular migration and invasion into the vasculature, triggering epithelial-mesenchymal transition, enhancing cancer stem cell-like properties, circumventing immune detection, and adapting to the heterogeneity of metastatic niches. This heavy reliance on SE-mediated transcription delineates a vulnerable target for therapeutic intervention in cancer cells. In this article, we review current insights into the characteristics, identification methodologies, formation, and activation mechanisms of SEs. We also elaborate the oncogenic roles and regulatory functions of SEs in the context of cancer metastasis. Ultimately, we discuss the potential of SEs as novel therapeutic targets and their implications in clinical oncology, offering insights into future directions for innovative cancer treatment strategies.


Asunto(s)
Elementos de Facilitación Genéticos , Regulación Neoplásica de la Expresión Génica , Metástasis de la Neoplasia , Neoplasias , Humanos , Neoplasias/patología , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/terapia , Animales , Epigénesis Genética , Terapia Molecular Dirigida , Transición Epitelial-Mesenquimal
6.
Nat Chem Biol ; 18(7): 733-741, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35654845

RESUMEN

N6-methyladenosine (6mA) is a DNA modification that has recently been found to play regulatory roles during mammalian early embryo development and mitochondrial transcription. We found that a dioxygenase CcTet from the fungus Coprinopsis cinerea is also a dsDNA 6mA demethylase. It oxidizes 6mA to the intermediate N6-hydroxymethyladenosine (6hmA) with robust activity of 6mA-containing duplex DNA (dsDNA) as well as isolated genomics DNA. Structural characterization revealed that CcTet utilizes three flexible loop regions and two key residues-D337 and G331-in the active pocket to preferentially recognize substrates on dsDNA. A CcTet D337F mutant protein retained the catalytic activity on 6mA but lost activity on 5-methylcytosine. Our findings uncovered a 6mA demethylase that works on dsDNA, suggesting potential 6mA demethylation in fungi and elucidating 6mA recognition and the catalytic mechanism of CcTet. The CcTet D337F mutant protein also provides a chemical biology tool for future functional manipulation of DNA 6mA in vivo.


Asunto(s)
Dioxigenasas , Eucariontes , 5-Metilcitosina/metabolismo , Animales , ADN/metabolismo , Metilación de ADN , Dioxigenasas/metabolismo , Eucariontes/metabolismo , Mamíferos/genética , Proteínas Mutantes/genética
7.
FASEB J ; 37(12): e23304, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37971426

RESUMEN

The phosphatase and tensin congeners (Pten) gene affects cell growth, cell proliferation, and rearrangement of connections, and it is closely related to cellular senescence, but it remains unclear the role of muscle-Pten gene in exercise against age-related deterioration in skeletal muscle and mortality induced by a high-salt diet (HSD). In here, overexpression and knockdown of muscle Pten gene were constructed by building MhcGAL4 /PtenUAS-overexpression and MhcGAL4 /PtenUAS-RNAi system in flies, and flies were given exercise training and a HSD for 2 weeks. The results showed that muscle Pten knockdown significantly reduced the climbing speed, climbing endurance, GPX activity, and the expression of Pten, Sirt1, PGC-1α genes, and it significantly increased the expression of Akt and ROS level, and impaired myofibril and mitochondria of aged skeletal muscle. Pten knockdown prevented exercise from countering the HSD-induced age-related deterioration of skeletal muscle. Pten overexpression has the opposite effect on skeletal muscle aging when compared to it knockdown, and it promoted exercise against HSD-induced age-related deterioration of skeletal muscle. Pten overexpression significantly increased lifespan, but its knockdown significantly decreased lifespan of flies. Thus, current results confirmed that differential expression of muscle Pten gene played an important role in regulating skeletal muscle aging and lifespan, and it also affected the adaptability of aging skeletal muscle to physical exercise since it determined the activity of muscle Pten/Akt pathway and Pten/Sirt1/PGC-1α pathway.


Asunto(s)
Condicionamiento Físico Animal , Sirtuina 1 , Animales , Sirtuina 1/metabolismo , Drosophila/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Condicionamiento Físico Animal/fisiología , Músculo Esquelético/metabolismo , Dieta , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo
8.
Neuroepidemiology ; 58(2): 75-91, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37980894

RESUMEN

BACKGROUND: Knowledge of stroke is essential to empower people to reduce their risk of these events. However, valid tools are required for accurate and reliable measurement of stroke knowledge. We aimed to systematically review contemporary stroke knowledge assessment tools and appraise their content validity, feasibility, and measurement properties. METHODS: The protocol was registered in PROSPERO (CRD42023403566). Electronic databases (MEDLINE, PsycInfo, CINAHL, Embase, Scopus, Web of Science) were searched to identify published articles (1 January 2015-1 March 2023), in which stroke knowledge was assessed using a validated tool. Two reviewers independently screened titles and abstracts prior to undertaking full-text review. COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) methods guided the appraisal of content validity (relevance, comprehensiveness, comprehensibility), feasibility, and measurement properties. RESULTS: After removing duplicates, the titles and abstracts of 718 articles were screened; 323 reviewed in full; with 42 included (N = 23 unique stroke knowledge tools). For content validity, all tools were relevant, two were comprehensive, and seven were comprehensible. Validation metrics were reported for internal consistency (n = 20 tools), construct validity (n = 17 tools), cross-cultural validity (n = 15 tools), responsiveness (n = 9 tools), reliability (n = 7 tools), structural validity (n = 3 tools), and measurement error (n = 1 tool). The Stroke Knowledge Test met all content validity criteria, with validation data for six measurement properties (n = 3 rated "Sufficient"). CONCLUSION: Assessment of stroke knowledge is not standardised and many tools lacked validated content or measurement properties. The Stroke Knowledge Test was the most comprehensive but requires updating and further validation for endorsement as a gold standard.


Asunto(s)
Accidente Cerebrovascular , Humanos , Reproducibilidad de los Resultados , Accidente Cerebrovascular/diagnóstico , Bases de Datos Factuales , Psicometría
9.
Pharmacol Res ; 199: 107039, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38123108

RESUMEN

Zinc is a crucial trace element in the human body, playing a role in various physiological processes such as oxidative stress, neurotransmission, protein synthesis, and DNA repair. The zinc transporters (ZnTs) family members are responsible for exporting intracellular zinc, while Zrt- and Irt-like proteins (ZIPs) are involved in importing extracellular zinc. These processes are essential for maintaining cellular zinc homeostasis. Imbalances in zinc metabolism have been linked to the development of neurodegenerative diseases. Disruptions in zinc levels can impact the survival and activity of neurons, thereby contributing to the progression of neurodegenerative diseases through mechanisms like cell apoptosis regulation, protein phase separation, ferroptosis, oxidative stress, and neuroinflammation. Therefore, conducting a systematic review of the regulatory network of zinc and investigating the relationship between zinc dysmetabolism and neurodegenerative diseases can enhance our understanding of the pathogenesis of these diseases. Additionally, it may offer new insights and approaches for the treatment of neurodegenerative diseases.


Asunto(s)
Proteínas de Transporte de Catión , Enfermedades Neurodegenerativas , Humanos , Proteínas de Transporte de Catión/genética , Proteínas de Transporte de Catión/metabolismo , Progresión de la Enfermedad , Homeostasis , Zinc/metabolismo
10.
Microb Cell Fact ; 23(1): 87, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38515152

RESUMEN

BACKGROUND: Natural tetramates are a family of hybrid polyketides bearing tetramic acid (pyrrolidine-2,4-dione) moiety exhibiting a broad range of bioactivities. Biosynthesis of tetramates in microorganisms is normally directed by hybrid polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) machineries, which form the tetramic acid ring by recruiting trans- or cis-acting thioesterase-like Dieckmann cyclase in bacteria. There are a group of tetramates with unique skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, which remain to be investigated for their biosynthetic logics. RESULTS: Herein, the tetramate type compounds bripiodionen (BPD) and its new analog, featuring the rare skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, were discovered from the sponge symbiotic bacterial Streptomyces reniochalinae LHW50302. Gene deletion and mutant complementation revealed the production of BPDs being correlated with a PKS-NRPS biosynthetic gene cluster (BGC), in which a Dieckmann cyclase gene bpdE was identified by sit-directed mutations. According to bioinformatic analysis, the tetramic acid moiety of BPDs should be formed on an atypical NRPS module constituted by two discrete proteins, including the C (condensation)-A (adenylation)-T (thiolation) domains of BpdC and the A-T domains of BpdD. Further site-directed mutagenetic analysis confirmed the natural silence of the A domain in BpdC and the functional necessities of the two T domains, therefore suggesting that an unusual aminoacyl transthiolation should occur between the T domains of two NRPS subunits. Additionally, characterization of a LuxR type regulator gene led to seven- to eight-fold increasement of BPDs production. The study presents the first biosynthesis case of the natural molecule with 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione skeleton. Genomic mining using BpdD as probe reveals that the aminoacyl transthiolation between separate NRPS subunits should occur in a certain population of NRPSs in nature.


Asunto(s)
Vías Biosintéticas , Sintasas Poliquetidas , Pirrolidinonas , Sintasas Poliquetidas/metabolismo , Bacterias/metabolismo , Piranos/metabolismo , Esqueleto/metabolismo , Péptido Sintasas/genética
11.
Environ Sci Technol ; 58(4): 2038-2047, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38241248

RESUMEN

Single-particle inductively coupled plasma mass spectrometry (spICP-MS) has been used to characterize metallic nanoparticles (NPs) assuming that all NPs are spherical and composed of pure element. However, environmental NPs generally do not meet these criteria, suggesting that spICP-MS may underestimate their true sizes. This study employed a system hyphenating the atomizer (ATM), differential mobility analyzer (DMA), and spICP-MS to characterize metallic NPs in tap water. Its performance was validated by using reference Au nanoparticles (AuNPs) and Ag-shelled AuNPs. The hyphenated system can determine the actual size and metal composition of both NPs with additional heating after ATM, while stand-alone spICP-MS misidentified the Ag-shelled AuNPs as smaller individual AgNPs and AuNPs. Dissolved metal ions could introduce artifact NPs after heating but could be eliminated by centrifugation. The hyphenated system was applied to characterize Fe-containing and Pb-containing NPs resulting from the corrosion of plumbing materials in tap water. The mode sizes of Fe-containing and Pb-containing NPs were determined to be 110 and 100 nm and the particle number concentrations were determined to be 4.99 × 107 and 1.40 × 106 #/mL, respectively. Cautions should be paid to potential changes in particle size induced by heating for metallic NPs with a low melting point or a high organic content.


Asunto(s)
Nanopartículas del Metal , Nanopartículas del Metal/química , Oro/química , Plomo , Ingeniería Sanitaria , Corrosión , Nebulizadores y Vaporizadores , Tamaño de la Partícula , Agua
12.
J Nat Prod ; 87(2): 396-403, 2024 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-38330072

RESUMEN

Six new sesquiterpene quinone/hydroquinone meroterpenoids, arenarialins A-F (1-6), were isolated from the marine sponge Dysidea arenaria collected from the South China Sea. Their chemical structures and absolute configurations were determined by HRMS and NMR data analyses coupled with DP4+ and ECD calculations. Arenarialin A (1) features an unprecedented tetracyclic 6/6/5/6 carbon skeleton, whereas arenarialins B-D (2-4) possess two rare secomeroterpene scaffolds. Arenarialins A-F showed inhibitory activity on the production of inflammatory cytokines TNF-α and IL-6 in LPS-induced RAW264.7 macrophages with arenarialin D regulating the NF-κB/MAPK signaling pathway.


Asunto(s)
Dysidea , Poríferos , Sesquiterpenos , Animales , Dysidea/química , Poríferos/química , Sesquiterpenos/farmacología , Sesquiterpenos/química , Antiinflamatorios/farmacología , FN-kappa B , Estructura Molecular
13.
BMC Geriatr ; 24(1): 370, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664604

RESUMEN

BACKGROUND: Intrinsic capacity (IC) is a comprehensive indicator of the overall well-being of older adults, and assessing of IC can help identify early stage of disability and tailor intervention to individual needs. However, there is a lack of effective and simple IC assessment tools. This study aimed to establish predictive scoring algorithms of IC to identify older adults at high risk of impaired functional ability. METHODS: We conducted a cross-sectional study in Southern Taiwan, measuring IC using 7 subitems: cognition, locomotion, vitality, vision, hearing, psychological well-being, and medication usage were measured. Functional ability outcomes included frailty, basic activities of daily living, and instrumental activities of daily living (IADL). The capability of 7 domains of IC in predicting functional ability was assessed by multivariable logistic regression. The prediction of capability of scoring algorithms was indicated by receiver operating characteristic (AUC) curves and measures of sensitivity and specificity. RESULTS: A total of 1,152 older adults were recruited and analyzed. Locomotion emerged as a significant predictor of IADL disability and worsening frailty. The IC-based weighted scoring algorism for predicting IADL demonstrated satisfactory capability (AUC: 0.80), as did the algorithm for predicting worsening frailty (AUC: 0.90). The optimal cutoff points for predicting IADL disability and frailty worse were estimated respectively at 13 and 16, with sensitivity/specificity values of 0.74/0.75 for the IADL prediction algorithm and 0.92/0.77 for the frailty prediction algorithm. CONCLUSION: Our 7-domain IC screening tool proves to be sensitive and practical for early identification of functional disability and frailty among community-dwelling older adults in Taiwan.


Asunto(s)
Actividades Cotidianas , Algoritmos , Evaluación Geriátrica , Vida Independiente , Humanos , Anciano , Masculino , Taiwán/epidemiología , Femenino , Estudios Transversales , Evaluación Geriátrica/métodos , Anciano de 80 o más Años , Fragilidad/diagnóstico , Fragilidad/epidemiología , Fragilidad/fisiopatología , Evaluación de la Discapacidad
14.
BMC Geriatr ; 24(1): 477, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38822234

RESUMEN

BACKGROUND: The World Health Organization (WHO) proposed the concept of intrinsic capacity (comprising composite physical and mental capacity) which aligns with their concepts of healthy aging and functional ability. Consequently, the WHO promotes the Integrated Care for Older People (ICOPE) framework as guidance for geriatric care. Consequently, each government should have a screening tool corresponding to ICOPE framework to promote geriatric care. The present study examined the initial psychometric properties of the Taiwan version of ICOPE (i.e., ICOPES-TW). METHODS: Older people (n = 1235; mean age = 72.63 years; 634 females [51.3%]) were approached by well-trained interviewers for participation. A number of measures were administered including the ICOPES-TW, WHOQOL-AGE (assessing quality of life [QoL]), Clinical Frailty Scale (assessing frailty), Barthel Index (assessing basic activity of daily living [BADL]), and Lawton Instrumental Activities of Daily Living Scale (assessing instrumental activity of daily living [IADL]). RESULTS: The ICOPES-TW had a two-factor structure (body functionality [eigenvalue = 1.932] and life adaptation [eigenvalue = 1.170]) as indicated by the results of exploratory factor analysis. Internal consistency of the ICOPES-TW was low (Cronbach's α = 0.55 [entire ICOPES-TW], 0.45 (body functionality factor), and 0.52 (life adaptation factor). ICOPES-TW scores were significantly (i) positively correlated with age (r = 0.321), IADL (r = 0.313), and frailty (r = 0.601), and (ii) negatively correlated with QoL (r=-0.447), and BADL (r=-0.447), with all p-values < 0.001. CONCLUSION: The ICOPES-TW could be a useful screening tool for healthcare providers to quickly evaluate intrinsic capacity for Taiwanese older people given that it has moderate to strong associations with age, BADL, IADL, QoL, and frailty.


Asunto(s)
Evaluación Geriátrica , Psicometría , Humanos , Femenino , Anciano , Masculino , Taiwán/epidemiología , Psicometría/métodos , Psicometría/normas , Evaluación Geriátrica/métodos , Anciano de 80 o más Años , Calidad de Vida/psicología , Actividades Cotidianas , Prestación Integrada de Atención de Salud , Tamizaje Masivo/métodos , Fragilidad/diagnóstico , Fragilidad/psicología , Encuestas y Cuestionarios
15.
J Plant Res ; 137(4): 589-604, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38739241

RESUMEN

Reevesia is an eastern Asian-eastern North American disjunction genus in the family Malvaceae s.l. and comprises approximately 25 species. The relationships within the genus are not well understood. Here, 15 plastomes representing 12 Reevesia species were compared, with the aim of better understanding the species circumscription and phylogenetic relationships within the genus and among genera in the family Malvaceae s.l. The 11 newly sequenced plastomes range between 161,532 and 161, 945 bp in length. The genomes contain 114 unique genes, 18 of which are duplicated in the inverted repeats (IRs). Gene content of these plastomes is nearly identical. All the protein-coding genes are under purifying selection in the Reevesia plastomes compared. The top ten hypervariable regions, SSRs, and the long repeats identified are potential molecular markers for future population genetic and phylogenetic studies. Phylogenetic analysis based on the whole plastomes confirmed the monophyly of Reevesia and a close relationship with Durio (traditional Bombacaceae) in subfamily Helicteroideae, but not with the morphologically similar genera Pterospermum and Sterculia (both of traditional Sterculiaceae). Phylogenetic relationships within Reevesia suggested that two species, R. pubescens and R. thyrsoidea, as newly defined, are not monophyletic. Six taxa, R. membranacea, R. xuefengensis, R. botingensis, R. lofouensis, R. longipetiolata and R. pycnantha, are suggested to be recognized.


Asunto(s)
Evolución Molecular , Filogenia , Plastidios , Plastidios/genética , Genoma de Plastidios/genética , Genes de Plantas , Análisis de Secuencia de ADN
16.
Chem Biodivers ; 21(5): e202400210, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38433548

RESUMEN

Currently, natural products are one of the priceless options for finding novel chemical pharmaceutical entities. Ellipticine is a naturally occurring alkaloid isolated from the leaves of Ochrosia elliptica Labill. Ellipticine and its derivatives are characterized by multiple biological activities. The purpose of this review was to provide a critical and systematic assessment of ellipticine and its derivatives as bioactive molecules over the last 60 years. Publications focused mainly on the total synthesis of alkaloids of this type without any evaluation of bioactivity have been excluded. We have reviewed papers dealing with the synthesis, bioactivity evaluation and mechanism of action of ellipticine and its derivatives. It was found that ellipticine and its derivatives showed cytotoxicity, antimicrobial ability, and anti-inflammatory activity, among which cytotoxicity toward cancer cell lines was the most investigated aspect. The inhibition of DNA topoisomerase II was the most relevant mechanism for cytotoxicity. The PI3K/AKT pathway, p53 pathway, and MAPK pathway were also closely related to the antiproliferative ability of these compounds. In addition, the structure-activity relationship was deduced, and future prospects were outlined. We are confident that these findings will lay a scientific foundation for ellipticine-based drug development, especially for anticancer agents.


Asunto(s)
Elipticinas , Elipticinas/farmacología , Elipticinas/química , Humanos , Relación Estructura-Actividad , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Proliferación Celular/efectos de los fármacos , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinfecciosos/farmacología , Antiinfecciosos/química , Estructura Molecular , Animales , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación
17.
Chem Biodivers ; 21(7): e202400832, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38712949

RESUMEN

Two new cytochalasans, marcytoglobosins A (1) and B (2) were isolated from the marine sponge associated fungus Chaetomium globosum 162105, along with six known compounds (3-8). The complete structures of two new compounds were determined based on 1D/2D NMR and HR-MS spectroscopic analyses coupled with ECD calculations. All eight isolates were evaluated for their antibacterial activity. Among them, compounds 3-8 displayed antibacterial effects against Staphylococcus epidermidis, Bacillus thuringiensis, Pseudomonas syringae pv. Actinidiae, Vibrio alginolyticus, and Edwardsiella piscicida with minimum inhibitory concentration (MIC) values ranging from 10 to 25 µg/mL.


Asunto(s)
Antibacterianos , Chaetomium , Pruebas de Sensibilidad Microbiana , Poríferos , Chaetomium/química , Animales , Poríferos/microbiología , Poríferos/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Citocalasinas/farmacología , Citocalasinas/química , Citocalasinas/aislamiento & purificación , Conformación Molecular
18.
Drug Dev Res ; 85(2): e22165, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38400652

RESUMEN

Isocryptomerin (ISO) is a flavonoid isolated from the natural medicine Selaginellae Herba, which has various pharmacological activities. This study investigated the antitumor effect and underlying molecular mechanism of ISO on hepatocellular carcinoma (HCC) HepG2 cells. The cell viability assay revealed that ISO has a considerable killing effect on HCC cell lines. The apoptosis assay showed that ISO induced mitochondria-dependent apoptosis through the Bad/cyto-c/cleaved (cle)-caspase-3/cleaved (cle)-PARP pathway. The network pharmacological analysis found 13 key target genes, and epidermal growth factor receptor (EGFR), AKT, mitogen-activated protein kinase (MAPK), and reactive oxygen species (ROS) signaling pathways were strongly associated with ISO against HCC. Further verification of the results showed that ISO induced apoptosis by increasing p-p38 and p-JNK expression and decreasing p-EGFR, p-SRC, p-ERK, and p-STAT3 expression. Furthermore, ISO induced G0/G1 phase arrest by downregulating p-AKT, Cyclin D, and CDK 4 expression and upregulating p21 and p27 expression in HepG2 cells. Moreover, ISO inhibited HepG2 cell migration by decreasing p-GSK-3ß, ß-catenin, and N-cadherin expression and increasing E-cadherin expression. Additionally, ISO promoted ROS accumulation in HepG2 cells, and ISO-induced apoptosis, arrest cell cycle, and inhibition of migration were reversed by an ROS scavenger, N-acetyl- l-cysteine. Overall, ISO induced cell apoptosis and cell cycle arrest and inhibited cell migration by ROS-mediated EGFR, AKT, and MAPK signaling pathways in HepG2 cells.


Asunto(s)
Carcinoma Hepatocelular , Flavonas , Neoplasias Hepáticas , Humanos , Células Hep G2 , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Farmacología en Red , Receptores ErbB
19.
Int J Mol Sci ; 25(12)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38928220

RESUMEN

We hypothesize that the injection of JP4-039, a mitochondria-targeted nitroxide, prior to irradiation of the mouse retina may decrease apoptosis and reduce neutrophil and macrophage migration into the retina. In our study, we aimed to examine the effects of JP4-039 in the mouse retina using fluorescent microscopy, a terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and flow cytometry. Forty-five mice and one eye per mouse were used. In Group 1, fluorescent microscopy was used to determine retinal uptake of 10 µL (0.004 mg/µL) of intravitreally injected BODIPY-labeled JP4-039 at 0, 15, and 60 min after injection. In Group 2, the TUNEL assay was performed to investigate the rate of apoptosis after irradiation in addition to JP4-039 injection, compared to controls. In Group 3, flow cytometry was used to determine the extent of inflammatory cell migration into the retina after irradiation in addition to JP4-039 injection, compared to controls. Maximal retinal uptake of JP4-039 was 15 min after intravitreal injection (p < 0.0001). JP4-039-treated eyes had lower levels of retinal apoptosis (35.8 ± 2.5%) than irradiated controls (49.0 ± 2.7%; p = 0.0066) and demonstrated reduced migration of N1 cells (30.7 ± 11.7% vs. 77.7 ± 5.3% controls; p = 0.004) and M1 cells (76.6 ± 4.2 vs. 88.1 ± 3.7% controls, p = 0.04). Pretreatment with intravitreally injected JP4-039 reduced apoptosis and inflammatory cell migration in the irradiated mouse retina, marking the first confirmed effect of this molecule in retinal tissue. Further studies may allow for safety profiling and potential use for patients with radiation retinopathy.


Asunto(s)
Apoptosis , Movimiento Celular , Mitocondrias , Retina , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Ratones , Retina/efectos de los fármacos , Retina/metabolismo , Retina/efectos de la radiación , Retina/patología , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/efectos de la radiación , Movimiento Celular/efectos de los fármacos , Movimiento Celular/efectos de la radiación , Ratones Endogámicos C57BL , Masculino , Óxidos de Nitrógeno/farmacología , Inflamación/patología
20.
Molecules ; 29(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38276618

RESUMEN

Sinomenine, an isoquinoline alkaloid extracted from the roots and stems of Sinomenium acutum, has been extensively studied for its derivatives as bioactive agents. This review concentrates on the research advancements in the biological activities and action mechanisms of sinomenine-related compounds until November 2023. The findings indicate a broad spectrum of pharmacological effects, including antitumor, anti-inflammation, neuroprotection, and immunosuppressive properties. These compounds are notably effective against breast, lung, liver, and prostate cancers, exhibiting IC50 values of approximately 121.4 nM against PC-3 and DU-145 cells, primarily through the PI3K/Akt/mTOR, NF-κB, MAPK, and JAK/STAT signaling pathways. Additionally, they manifest anti-inflammatory and analgesic effects predominantly via the NF-κB, MAPK, and Nrf2 signaling pathways. Utilized in treating rheumatic arthritis, these alkaloids also play a significant role in cardiovascular and cerebrovascular protection, as well as organ protection through the NF-κB, Nrf2, MAPK, and PI3K/Akt/mTOR signaling pathways. This review concludes with perspectives and insights on this topic, highlighting the potential of sinomenine-related compounds in clinical applications and the development of medications derived from natural products.


Asunto(s)
Alcaloides , Morfinanos , Masculino , Humanos , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-akt , Factor 2 Relacionado con NF-E2 , Fosfatidilinositol 3-Quinasas , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Morfinanos/farmacología , Serina-Treonina Quinasas TOR , Alcaloides/farmacología
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