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1.
Chem Rev ; 123(7): 3944-3975, 2023 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-36108155

RESUMEN

Micro-/nanorobots (MNRs) can be autonomously propelled on demand in complex biological environments and thus may bring revolutionary changes to biomedicines. Fluorescence has been widely used in real-time imaging, chemo-/biosensing, and photo-(chemo-) therapy. The integration of MNRs with fluorescence generates fluorescent MNRs with unique advantages of optical trackability, on-the-fly environmental sensitivity, and targeting chemo-/photon-induced cytotoxicity. This review provides an up-to-date overview of fluorescent MNRs. After the highlighted elucidation about MNRs of various propulsion mechanisms and the introductory information on fluorescence with emphasis on the fluorescent mechanisms and materials, we systematically illustrate the design and preparation strategies to integrate MNRs with fluorescent substances and their biomedical applications in imaging-guided drug delivery, intelligent on-the-fly sensing and photo-(chemo-) therapy. In the end, we summarize the main challenges and provide an outlook on the future directions of fluorescent MNRs. This work is expected to attract and inspire researchers from different communities to advance the creation and practical application of fluorescent MNRs on a broad horizon.


Asunto(s)
Sistemas de Liberación de Medicamentos , Fluorescencia
2.
Nano Lett ; 24(20): 5958-5967, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38738749

RESUMEN

Micro/nanorobots hold the potential to revolutionize biomedicine by executing diverse tasks in hard-to-reach biological environments. Nevertheless, achieving precise drug delivery to unknown disease sites using swarming micro/nanorobots remains a significant challenge. Here we develop a heterogeneous swarm comprising sensing microrobots (sensor-bots) and drug-carrying microrobots (carrier-bots) with collaborative tasking capabilities for precise drug delivery toward unknown sites. Leveraging robust interspecific hydrodynamic interactions, the sensor-bots and carrier-bots spontaneously synchronize and self-organize into stable heterogeneous microswarms. Given that the sensor-bots can create real-time pH maps employing pH-responsive structural-color changes and the doxorubicin-loaded carrier-bots exhibit selective adhesion to acidic targets via pH-responsive charge reversal, the sensor-carrier microswarm, when exploring unknown environments, can detect and localize uncharted acidic targets, guide itself to cover the area, and finally deploy therapeutic carrier-bots precisely there. This versatile platform holds promise for treating diseases with localized acidosis and inspires future theranostic microsystems with expandability, task flexibility, and high efficiency.


Asunto(s)
Doxorrubicina , Sistemas de Liberación de Medicamentos , Doxorrubicina/química , Doxorrubicina/farmacología , Concentración de Iones de Hidrógeno , Acidosis , Humanos , Portadores de Fármacos/química , Robótica
3.
J Cell Mol Med ; 26(20): 5330-5334, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36050866

RESUMEN

Conotoxins are promising neuropharmacological tools and drug candidates due to their high efficiency and specificity in targeting ion channels or neurotransmitter receptors. In this study, a novel O2 -superfamily conotoxin, Lt7b, was synthesized and its pharmacological functions were evaluated. Lt7b with three modified amino acids and three disulfide bonds was successfully synthesized. CD spectra showed that Lt7b had a typical α-helix in the secondary structure. Patch clamp experiments on rat DRG neurons showed that Lt7b could significantly inhibit calcium currents with an IC50 value of 856 ± 95 nM. Meanwhile, 10 µM Lt7b could significantly increase the sodium currents by 77 ± 8%, but it had no obvious effects on the potassium currents in DRG neurons. In addition, patch clamp experiments on ion channel subtypes showed that 10 µM Lt7b could inhibit 7.0 ± 1.2%, 8.0 ± 1.5%, 4.6 ± 3.4%, and 9.5 ± 0.1% of the hCav 1.2, hCav 2.1, hCav 2.2, and hCav 3.2 currents, respectively, while it did not increase the rNav 1.7, rNav 1.8, hNav 1.5, hNav 1.7, and hNav 1.8 currents. Lt7b had no obvious toxicity to HaCaT and ND7/23 cells up to 1 mM and significantly increased the pain threshold at the testing time of 0.5-4 h in a dose-dependent manner in the mouse hotplate assay. This novel conotoxin Lt7b may be a useful tool for ion channel studies and analgesic drug development.


Asunto(s)
Analgésicos , Conotoxinas , Aminoácidos , Analgésicos/farmacología , Animales , Calcio/metabolismo , Conotoxinas/química , Conotoxinas/farmacología , Disulfuros , Ratones , Potasio , ARN , Ratas , Receptores de Neurotransmisores , Sodio
4.
Phys Rev Lett ; 127(8): 080603, 2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34477397

RESUMEN

The study of liquid-liquid phase transitions has attracted considerable attention. One interesting example of this phenomenon is phosphorus, for which the existence of a first-order phase transition between a low density insulating molecular phase and a conducting polymeric phase has been experimentally established. In this Letter, we model this transition by an ab initio quality molecular dynamics simulation and explore a large portion of the liquid section of the phase diagram. We draw the liquid-liquid coexistence curve and determine that it terminates into a second-order critical point. Close to the critical point, large coupled structure and electronic structure fluctuations are observed.

5.
J Cell Physiol ; 235(3): 2557-2568, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31498440

RESUMEN

Glycochenodeoxycholate (GCDA) is closely associated with carcinogenesis and chemoresistance of hepatocellular carcinoma (HCC). Signal transducer and activator of transcription 3 (STAT3), a transcription factor, is involved in various human tumors. Whether GCDA induces chemoresistance through STAT3 and the mechanism of action remains elusive. In this study, we firstly found that the expression level of STAT3 has a positive correlation with chemoresistance of HCC cells. Moreover, GCDA can upregulate the expression of STAT3 protein. Hence, we suspect that GCDA may induce chemoresistance of HCC cells via STAT3. Mechanistically, GCDA stimulates phosphorylation of STAT3 at Ser727 site and mediates pSer727-STAT3 protein to translocate and aggregate in the nucleus, which is important for cell survival. When Ser727 of STAT3 mutated to Asp, the capacity of STAT3 to accumulate in the nucleus was attenuated, STAT3-induced cell survival was impaired and GCDA-induced chemoresistance was abolished. In addition, while activation of extracellular signal-regulated kinase 1/2 (ERK1/2) was inhibited by PD98059, phosphorylation of STAT3 at Ser727 induced by GCDA was suppressed. Taken together, these data demonstrate that GCDA-enhanced survival of liver cancer cells may occur through the activation of STAT3 by phosphorylation at Ser727 site via mitogen-activated protein kinase/ERK1/2 pathway, which may contribute to the progression of human liver cancer and chemoresistance.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Ácido Glicoquenodesoxicólico/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Factor de Transcripción STAT3/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Supervivencia Celular/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Flavonoides/farmacología , Fluorouracilo/efectos adversos , Fluorouracilo/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Sistema de Señalización de MAP Quinasas/genética , Fosforilación/efectos de los fármacos
6.
J Cell Physiol ; 234(9): 16592-16600, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30805927

RESUMEN

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in adults. Basic leucine zipper and W2 domains 2 (BZW2) is a member of the basic-region leucine zipper (bZIP) superfamily of transcription factors. Here, we found that BZW2 expression was substantially increased in both human HCC tissues and cell lines, which was correlated with the clinical progression of patients with HCC. Silence of BZW2 in HCC cells by infecting with the lentivirus for delivering BZW2 shRNA (short hairpin RNA), prohibits cell progression, as determined by the suppressed cell proliferation, clonality, invasion, and increased cell apoptosis. Furthermore, overexpression of BZW2 promotes drug resistance of HCC cells, as shown by the attenuated suppression of cell viability and invasion following rapamycin (RAPA) treatment. Mechanistically, overexpression (or silence) of BZW2 in HCC cells significantly stimulates (or decreases) the activation of the PI3K/AKT/mTOR signaling pathway, which is responsible for HCC progression. Thus, increased BZW2 expression in HCC can induce HCC progression and drug resistance via stimulating the PI3K/AKT/mTOR pathway, which may represent a new therapeutic target for HCC.

7.
J Cell Physiol ; 234(9): 15934-15940, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30741422

RESUMEN

Nicotine is a major carcinogen in cigarettes, which can enhance cell proliferation and metastasis and increase the chemoresistance of cancer cells. Our previous data found that nicotine promotes cell survival in lung cancer by affecting the expression of antiapoptotic protein Mcl-1, suggesting that the Mcl-1 may be a therapeutic target for patients with lung cancer. In this study, we found that the effects of drug resistance on nicotine-induced lung cancer cell lines were shown to influence the phosphorylation of Mcl-1. Moreover, nicotine induces Mcl-1 phosphorylation exclusively at the T163 site, which results in enhancement of the antiapoptotic activity of Mcl-1 and increased cell survival. Meanwhile, nicotine can reduce the sensitivity of H1299 cells to CDDP via enhancement of the binding of Mcl-1 to Bak, which inhibits the proapoptotic effect of Bak and ultimately leads to increased survival and drug resistance of lung cancer cells. Thus, nicotine-induced cell survival and chemoresistance may occur in a mechanism by stimulating Mcl-1 phosphorylation and its interaction with Bak, which may contribute to improving the efficacy of chemotherapy in the treatment of human lung cancer.

8.
J Cell Physiol ; 234(7): 10899-10906, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30548625

RESUMEN

OBJECTIVE: Glycochenodeoxycholate acid (GCDA) is a toxic component in bile salts. It plays an important role in the development and progression of liver cancer. In this study, we investigated the underlying mechanism of GCDA in hepatocarcinogenesis and chemotherapy resistance. MATERIALS AND METHODS: Cell proliferation was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and clonality by Ki-67 and colony-formation assay. Apoptosis was examined by flow cytometry. Real-time polymerase chain reaction (PCR) and western blot analysis were used to measure messenger RNA and protein levels, respectively. Short hairpin RNA was used to silence signal transducer and activator of transcription 3 (Stat3) expression. RESULTS: Bile salts (GCDA) promoted the proliferation of hepatocellular carcinoma (HCC) cells (HepG2 and QGY-7703), and GCDA treatment reduced the chemosensitivity of 5-fluorouracil (5FU) in HepG2 and QGY-7703 cells. GCDA upregulated the expression of antiapoptosis proteins Mcl-1/Survivin/Bcl-2. GCDA had no discernible effect on basal protein level or subcellular localization of phosphorylated Stat3. 5FU increased the apoptosis of HepG2 cells with silenced Stat3 expression, but GCDA-induced chemoresistance was not reversed. CONCLUSIONS: GCDA-reduced HCC cell chemosensitivity may occur by upregulating antiapoptosis proteins Mcl-1/Survivin/Bcl-2. Stat3 may be a target for enhancing the chemosensitivity of hepatocellular carcinoma cells, but GCDA-induced chemoresistance is independent of Stat3.


Asunto(s)
Carcinoma Hepatocelular/patología , Resistencia a Antineoplásicos/efectos de los fármacos , Ácido Glicoquenodesoxicólico/toxicidad , Neoplasias Hepáticas/patología , Antimetabolitos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Fluorouracilo/farmacología , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/genética , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Survivin/genética , Survivin/metabolismo
9.
Analyst ; 144(2): 536-542, 2019 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-30406221

RESUMEN

Fluorescent probes are powerful tools for investigating reactive oxygen species (ROS) in living organisms. The overproduced "primary" ROS of superoxide anions (O2˙-) cause a chain of oxidative damage. In order to monitor O2˙- level fluctuations in living cells, we synthesized two reaction-type probes of TPA-DHP-1,2,3 and TPA-PPA-1,2,3, which were composed of an electron-rich triphenylamine (TPA) and the very active functional groups of dihydropyridine (DHP) and pyridinium (PPA). Intriguingly, DHP and PPA were able to carry out easy proton abstractions and nucleophilic reactions in the presence of O2˙-, resulting in the corresponding products with sharp wavelength shifts, and elevated fluorescence intensities. Therefore, undesirable background fluorescence interference can be reduced during the monitoring and imaging process. Meanwhile, the developed dual-channel monitoring strategy not only provides observations of the O2˙- level fluctuations, but could also be employed to image the dynamic accumulation process of probes in the different cell organelles. Therefore, the design could provide a simple, accurate and universal platform for biological applications in future research work.


Asunto(s)
Colorantes Fluorescentes/química , Colorantes Fluorescentes/metabolismo , Imagen Óptica/métodos , Superóxidos/metabolismo , Arsenicales/química , Células HeLa , Humanos , Modelos Moleculares , Conformación Molecular , Fenómenos Ópticos , Factores de Tiempo
10.
Tumour Biol ; 39(7): 1010428317712102, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28681695

RESUMEN

In cholestasis, increases in bile acid levels result in the generation of reactive oxygen species and the induction of DNA damage and mutation. It is believed that bile acid accumulation is associated with liver tumorigenesis. However, the mechanism that underpins this phenomenon remains to be elucidated. Mcl-1, which is overexpressed in hepatic cells, is a pro-survival member of the Bcl-2 family. In this study, we observed that Mcl-1 potently suppresses the repair of bile acid-induced abasic (apurinic/apyrimidinic) sites in DNA lesions. Upon exposure of hepatic cells to glycochenodeoxycholate, one of the major conjugated human bile acids, we observed an increase in AP site accumulation along with induction of poly(ADP-ribose) polymerase and XRCC1 ( X-Ray Repair Cross Complementing 1). In addition, accumulation of Mcl-1 was observed in the nuclei of QGY-7703 cells in response to glycochenodeoxycholate stimulation. Knockdown of endogenous Mcl-1 by RNA interference significantly accelerated the repair of DNA lesions in glycochenodeoxycholate-treated cells. However, unlike XRCC1, poly(ADP-ribose) polymerase was induced following Mcl-1 knockdown. Conversely, poly(ADP-ribose) polymerase suppression was observed following glycochenodeoxycholate treatment of cells overexpressing Mcl-1. Moreover, AP-site counting analyses revealed that DNA repair activity was enhanced in cells overexpressing poly(ADP-ribose) polymerase under glycochenodeoxycholate stress conditions. It is well known that poly(ADP-ribose) polymerase plays a crucial role in the base excision repair pathway. Thus, our findings suggest that Mcl-1 suppresses base excision repair by inhibiting poly(ADP-ribose) polymerase induction following glycochenodeoxycholate-induced DNA damage. These results potentially explain how bile acid accumulation results in genetic instability and carcinogenesis.


Asunto(s)
Colestasis/genética , Proteínas de Unión al ADN/genética , Neoplasias Hepáticas/genética , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/genética , Poli(ADP-Ribosa) Polimerasas/genética , Ácido Apurínico/genética , Ácidos y Sales Biliares/normas , Ácidos y Sales Biliares/toxicidad , Colestasis/metabolismo , Colestasis/patología , Daño del ADN/efectos de los fármacos , Reparación del ADN/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Ácido Glicoquenodesoxicólico/toxicidad , Células Hep G2 , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Hepatocitos/patología , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Especies Reactivas de Oxígeno/metabolismo , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X
11.
J Immunol ; 195(7): 3110-8, 2015 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-26324776

RESUMEN

Studies have shown that the basal chordate amphioxus possesses an extraordinarily complex TLR system, including 39 TLRs and at least 40 Toll/IL-1R homologous region (TIR) adaptors. Besides homologs to MyD88 and TIR domain-containing adaptor molecule (TICAM), most amphioxus TIR adaptors exhibit domain architectures that are not observed in other species. To reveal how these novel TIR adaptors function in amphioxus Branchiostoma belcheri tsingtauense (bbt), four representatives, bbtTIRA, bbtTIRB, bbtTIRC, and bbtTIRD, were selected for functional analyses. We found bbtTIRA to show a unique inhibitory role in amphioxus TICAM-mediated pathway by interacting with bbtTICAM and bbt receptor interacting protein 1b, whereas bbtTIRC specifically inhibits the amphioxus MyD88-dependent pathway by interacting with bbtMyD88 and depressing the polyubiquitination of bbt TNFR-associated factor 6. Although both bbtTIRB and bbtTIRD are located on endosomes, the TIR domain of bbtTIRB can interact with bbtMyD88 in the cytosol, whereas the TIR domain of bbtTIRD is enclosed in endosome, suggesting that bbtTIRD may be a redundant gene in amphioxus. This study indicated that most expanded TIR adaptors play nonredundant regulatory roles in amphioxus TLR signaling, adding a new layer to understanding the diversity and complexity of innate immunity at basal chordate.


Asunto(s)
Inmunidad Innata/genética , Interleucina-1/genética , Anfioxos/inmunología , FN-kappa B/metabolismo , Receptores Toll-Like/genética , Animales , Secuencia de Bases , Sitios de Unión/genética , Línea Celular , Células HEK293 , Humanos , Inmunidad Innata/inmunología , Inflamación/inmunología , Anfioxos/genética , Datos de Secuencia Molecular , Factor 88 de Diferenciación Mieloide/genética , FN-kappa B/antagonistas & inhibidores , Regiones Promotoras Genéticas/genética , Unión Proteica/genética , Estructura Terciaria de Proteína/genética , Análisis de Secuencia de ADN , Transducción de Señal/inmunología , Factor 6 Asociado a Receptor de TNF/metabolismo , Receptores Toll-Like/metabolismo , Ubiquitinación
12.
J Phys Chem A ; 121(6): 1351-1361, 2017 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-28127960

RESUMEN

We proposed and implemented a combined molecular dynamics and coordinate driving (MD/CD) method for automatically searching multistep reaction pathways of chemical reactions. In this approach, the molecular dynamic (MD) method at the molecular mechanics (MM) or semiempirical quantum mechanical (QM) level is employed to explore the conformational space of the minimum structures, and the modified coordinate driving (CD) method is used to build reaction pathways for representative conformers. The MD/CD method is first applied to two model reactions (the Claisen rearrangement and the intermolecular aldol reaction). By comparing the obtained results with those of the existing methods, we found that the MD/CD method has a comparable performance in searching low-energy reaction pathways. Then, the MD/CD method is further applied to investigate two reactions: the electrocyclic reaction of benzocyclobutene-7-carboxaldehyde and the intramolecular Diels-Alder reaction of ketothioester with 11 effectively rotatable single bonds. For the first reaction, our results can correctly account for its torquoselectivity. For the second one, our method predicts eight reaction channels, leading to eight different stereo- and regioselective products. The MD/CD method is expected to become an efficient and cost-effective theoretical tool for automatically searching low-energy reaction pathways for relatively complex chemical reactions.

13.
BMC Complement Altern Med ; 17(1): 477, 2017 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-28978315

RESUMEN

BACKGROUND: The aim of this in vitro study was to measure the enhanced anticancer effects of Res (resveratrol) on PA (paclitaxel) in HepG2 human liver cancer cells. METHODS: The MTT (thiazolyl blue tetrazolium bromide, 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide), flow cytometry, qPCR (real-time quantitative polymerase chain reaction) and western blot assay were used for cells growth inhibitory effects, cells apoptosis (DNA content of sub-G1), mRNA and protein expressions, respectively. RESULTS: The 10 µg/mL of Res had no growth inhibitory effect on Nthy-ori 3-1 normal cells or HepG2 cancer cells meanwhile the 5 or 10 µg/mL of PA also had no growth inhibitory effect on Nthy-ori 3-1 normal cells. Where as PA-L (5 µg/mL) and PA-H (10 µg/mL) had the growth inhibitory effects in HepG2 cancer cells, and Res increase these growth inhibitory effects. By flow cytometry experiment, after Res (5 µg/mL) + PA-H (10 µg/mL) treatment, the HepG2 cells showed the most apoptosis in cells as compared to other treatments groups, and after additionally treated with Res, both the apoptosis cells of two concentrations PA were raised. As PA raised it also raised the mRNA and protein expressions of caspase-3, caspase-8, caspase-9, Bax (Bcl-2 assaciated X protein), p53, p21, IκB-α (inhibitor of NF-κB alpha), Fas (factor associated suicide), FasL (factor associated suicide ligand), TIMP-1 (tissue inhibitor of metalloproteinases 1), TIMP-2 (tissue inhibitor of metalloproteinases 2) and decrease Bcl-2 (B cell leukemia 2), Bcl-xL (B cell leukemia extra large), HIAP-1 (cIAP-1, cellular inhibitor of apoptosis 1), HIAP-2 (cIAP-2, cellular inhibitor of apoptosis 2), NF-κB (nuclear factor kappa B), COX-2 (cyclooxygenase 2), iNOS (inducible nitric oxide synthase), MMP-2 (metalloproteinase 2), MMP-9 (metalloproteinase 9), EGF (epidermal growth factor), EGFR (epidermal growth factor receptor), VEGF (vascular endothelial growth factor), Fit-1 (VEGFR-1, vascular endothelial growth factor receptor 1). Meanwhile, the 5 µg/mL of Res could enhance these mRNA expressions changes as compared to the control cells. CONCLUSION: From these results, we can conclude that Res could raise the anticancer effects of PA in HepG2 cells, Res could be used as a good sensitizing agent for PA.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Neoplasias Hepáticas/metabolismo , Paclitaxel/farmacología , Estilbenos/farmacología , Apoptosis/efectos de los fármacos , Sinergismo Farmacológico , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/genética , Células Hep G2 , Humanos , ARN Mensajero/análisis , ARN Mensajero/genética , ARN Mensajero/metabolismo , Resveratrol
15.
Biochem Biophys Res Commun ; 480(3): 334-340, 2016 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-27756618

RESUMEN

Molecule-targeted therapy has become the research focus for hepatocellular carcinoma (HCC). Persistent PI3K-AKT activation is often detected in HCC, representing a valuable oncotarget for treatment. Here, we tested the anti-HCC activity by a potent AKT inhibitor: AKT inhibitor 1/2 (AKTi-1/2). In both established (HepG2 and Huh-7) and primary human HCC cells, treatment with AKTi-1/2 inhibited cell survival and proliferation, but induced cell apoptosis. AKTi-1/2 blocked AKT-mTOR activation, yet simultaneously provoked cytoprotective autophagy in HCC cells. The latter was evidenced by ATG-5 and Beclin-1 upregulation, p62 downregulation as well as LC3B-GFP puncta formation. Autophagy inhibition, via pharmacological inhibitors (3-methyladenine, ammonium chloride, and bafilomycin A1) or Beclin-1 siRNA knockdown, significantly potentiated AKTi-1/2-induced HepG2 cell death and apoptosis. In nude mice, AKTi-1/2 intraperitoneal injection inhibited HepG2 tumor growth. Significantly, its anti-tumor activity in vivo was further sensitized when combined with Beclin-1 shRNA knockdown in HepG2 tumors. Together, these results demonstrate that autophagy activation serves as a main resistance factor of AKTi-1/2 in HCC cells. Autophagy prevention therefore sensitizes AKTi-1/2-induced anti-HCC activity in vitro and in vivo.


Asunto(s)
Antineoplásicos/administración & dosificación , Autofagia/efectos de los fármacos , Bencilaminas/efectos adversos , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Quinoxalinas/efectos adversos , Animales , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Sinergismo Farmacológico , Femenino , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Terapia Molecular Dirigida/métodos , Resultado del Tratamiento
16.
Chem Sci ; 15(9): 3382-3392, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38425540

RESUMEN

The anomalous λ-transition of liquid sulfur, which is supposed to be related to the transformation of eight-membered sulfur rings into long polymeric chains, has attracted considerable attention. However, a detailed description of the underlying dynamical polymerization process is still missing. Here, we study the structures and the mechanism of the polymerization processes of liquid sulfur across the λ-transition as well as its reverse process of formation of the rings. We do so by performing ab initio-quality molecular dynamics simulations thanks to a combination of machine learning potentials and state-of-the-art enhanced sampling techniques. With our approach, we obtain structural results that are in good agreement with the experiments and we report precious dynamical insights into the mechanisms involved in the process.

17.
Biochim Biophys Acta Mol Basis Dis ; 1870(5): 167152, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38582012

RESUMEN

Intrahepatic cholangiocarcinoma (ICC) is a kind of hepatobiliary tumor that is increasing in incidence and mortality. The gut microbiota plays a role in the onset and progression of cancer, however, the specific mechanism by which the gut microbiota acts on ICC remains unclear. In this study, feces and plasma from healthy controls and ICC patients were collected for 16S rRNA sequencing or metabolomics analysis. Gut microbiota analysis showed that gut microbiota abundance and biodiversity were altered in ICC patients compared with controls. Plasma metabolism analysis showed that the metabolite glutamine content of the ICC patient was significantly higher than that of the controls. KEGG pathway analysis showed that glutamine plays a vital role in ICC. In addition, the use of antibiotics in ICC animals further confirmed that changes in gut microbiota affect changes in glutamine. Further experiments showed that supplementation with glutamine inhibited ferroptosis and downregulated ALK5 and NOX1 expression in HuCCT1 cells. ALK5 overexpression or NOX1 overexpression increased NOX1, p53, PTGS2, ACSL4, LPCAT3, ROS, MDA and Fe2+ and decreased FTH1, SLC7A11 and GSH. Knockdown of NOX1 suppressed FIN56-induced ferroptosis. In vivo, supplementation with glutamine promoted tumor growth. Overexpression of ALK5 repressed tumor growth and induced ferroptosis in nude mice, which could be reversed by the addition of glutamine. Our results suggested that the gut microbiota altered glutamine metabolism to inhibit ferroptosis in ICC by regulating the ALK5/NOX1 axis.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Ferroptosis , Microbioma Gastrointestinal , Glutamina , NADPH Oxidasa 1 , Colangiocarcinoma/patología , Colangiocarcinoma/metabolismo , Colangiocarcinoma/microbiología , Colangiocarcinoma/tratamiento farmacológico , Ferroptosis/efectos de los fármacos , Humanos , Glutamina/metabolismo , NADPH Oxidasa 1/metabolismo , NADPH Oxidasa 1/genética , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Neoplasias de los Conductos Biliares/patología , Neoplasias de los Conductos Biliares/metabolismo , Neoplasias de los Conductos Biliares/microbiología , Ratones , Masculino , Línea Celular Tumoral , Receptores de Activinas Tipo I/metabolismo , Receptores de Activinas Tipo I/genética , Ratones Desnudos , Femenino , Persona de Mediana Edad , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Receptor Tipo I de Factor de Crecimiento Transformador beta
18.
Adv Sci (Weinh) ; : e2401711, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38868929

RESUMEN

Individual differences in size, experience, and task specialization in natural swarms often result in heterogeneity and hierarchy, facilitating efficient and coordinated task accomplishment. Drawing inspiration from this phenomenon, a general strategy is proposed for organizing magnetic micro/nanorobots (MNRs) with apparent differences in size, shape, and properties into cohesive microswarms with tunable heterogeneity, controlled spatial hierarchy, and collaborative tasking capability. In this strategy, disparate magnetic MNRs can be manipulated to show reversible transitions between synchronization and desynchronization by elaborately regulating parameter sets of the rotating magnetic field. Utilizing these transitions, alongside local robust hydrodynamic interactions, diverse heterospecific pairings of disparate magnetic MNRs can be organized into heterogeneous microswarms, and their spatial organization can be dynamically adjusted from egalitarian to leader-follower-like hierarchies on the fly, both in open space and complex microchannels. Furthermore, when specializing the disparate MNRs with distinct functions ("division of labor") such as sensing and drug carrying, they can execute precise drug delivery targeting unknown sites in a collaborative sensing-navigating-cargo dropping sequence, demonstrating significant potential for precise tumor treatment. These findings highlight the critical roles of attribute differences and hierarchical organization in designing efficient swarming micro/nanorobots for biomedical applications.

19.
J Immunol ; 187(8): 3962-71, 2011 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-21911601

RESUMEN

Recently, receptor interacting protein (RIP)-1 has been recognized as an intracellular sensor at the crossroads of apoptosis, necroptosis, and cell survival. To reveal when this crucial molecule originated and how its function in integrating stress signals evolved, in this study we report on two RIP1 homologs in Chinese amphioxus (Branchiostoma belcheri tsingtauense), designated B. belcheri tsingtauense RIP1a and B. belcheri tsingtauense RIP1b. Phylogenetic analysis indicates that they are generated by domain recombination and lineage-specific duplication. Similar to human RIP1, both B. belcheri tsingtauense RIP1a and B. belcheri tsingtauense RIP1b activate NF-κB in a kinase activity-independent manner and induce apoptosis through the Fas-associated death domain protein-caspase cascade. Moreover, we found that the natural point mutation of Q to I in the RIP homotypic interaction motif of B. belcheri tsingtauense RIP1a provides negative feedback for amphioxus RIP1-mediated signaling. Thus, our study not only suggests that RIP1 has emerged as a molecular switch in triggering cell death or survival in a basal chordate, but also adds new insights into the regulation mechanisms of RIP1-related signaling, providing a novel perspective on human diseases mediated by RIP1.


Asunto(s)
Apoptosis/genética , Linaje de la Célula , Supervivencia Celular/genética , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Transducción de Señal/genética , Secuencia de Aminoácidos , Animales , Apoptosis/inmunología , Secuencia de Bases , Cordados no Vertebrados , Técnica del Anticuerpo Fluorescente , Células HEK293 , Humanos , Inmunoprecipitación , Hibridación in Situ , Datos de Secuencia Molecular , Filogenia , Proteína Serina-Treonina Quinasas de Interacción con Receptores/inmunología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección
20.
Nanomaterials (Basel) ; 13(8)2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37110955

RESUMEN

Self-propelled chemical micro/nanomotors (MNMs) have demonstrated considerable potential in targeted drug delivery, (bio)sensing, and environmental remediation due to their autonomous nature and possible intelligent self-targeting behaviors (e.g., chemotaxis and phototaxis). However, these MNMs are commonly limited by their primary propulsion mechanisms of self-electrophoresis and electrolyte self-diffusiophoresis, making them prone to quenching in high electrolyte environments. Thus, the swarming behaviors of chemical MNMs in high-electrolyte media remain underexplored, despite their potential to enable the execution of complex tasks in high-electrolyte biological media or natural waters. In this study, we develop ultrasmall tubular nanomotors that exhibit ion-tolerant propulsions and collective behaviors. Upon vertical upward UV irradiation, the ultrasmall Fe2O3 tubular nanomotors (Fe2O3 TNMs) demonstrate positive superdiffusive photogravitaxis and can further self-organize into nanoclusters near the substrate in a reversible manner. After self-organization, the Fe2O3 TNMs exhibit a pronounced emergent behavior, allowing them to switch from random superdiffusions to ballistic motions near the substrate. Even at a high electrolyte concentration (Ce), the ultrasmall Fe2O3 TNMs retain a relatively thick electrical double layer (EDL) compared to their size, and the electroosmotic slip flow in their EDL is strong enough to propel them and induce phoretic interactions among them. As a result, the nanomotors can rapidly concentrate near the substrate and then gather into motile nanoclusters in high-electrolyte environments. This work opens a gate for designing swarming ion-tolerant chemical nanomotors and may expedite their applications in biomedicine and environmental remediation.

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