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1.
J Med Chem ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39091011

RESUMO

As an oleanolic acid derivative, CDDO-Me lacks selectivity for tumors. Based on the high reactive oxygen species (ROS) level in cancer cells, compound 4 was selected from 17 new CDDO arylboronate ester derivatives. A preliminary study revealed that 4 displayed the highest selectivity for cancer cells. Furthermore, 4 could be transformed to 4H by ROS to increase its covalent binding ability and antiproliferation effect (IC50 of 2.11 vs 0.37 µM) in BGC-823 cells. Interestingly, 4 increased ROS levels to induce apoptosis in BGC-823 cells. Moreover, the LD50 of 4 (91.2 mg/kg) was much greater than that of CDDO-Me (61.7 mg/kg) in ICR mice. A pharmacokinetic study indicated that 4 could be transformed to 4H in vivo. In addition, 4 exhibited a greater tumor inhibition rate (86.2%) than CDDO-Me (51.7%). Overall, the design of 4 provided an effective modification strategy for CDDO to increase the selectivity for cancer cells.

2.
Biomater Sci ; 12(14): 3622-3632, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38855985

RESUMO

Chemodynamic therapy (CDT) has outstanding potential as a combination therapy to treat cancer. However, the effectiveness of CDT in the treatment of solid tumors is limited by the overexpression of glutathione (GSH) in the tumor microenvironment (TME). GSH overexpression diminishes oxidative stress and attenuates chemotherapeutic drug-induced apoptosis in cancer cells. To counter these effects, a synergistic CDT/chemotherapy cancer treatment, involving the use of a multifunctional bioreactor of hollow manganese dioxide (HMnO2) loaded with cisplatin (CDDP), was developed. Metal nanoenzymes that can auto-degrade to produce Mn2+ exhibit Fenton-like, GSH-peroxidase-like activity, which effectively depletes GSH in the TME to attenuate the tumor antioxidant capacity. In an acidic environment, Mn2+ catalyzed the decomposition of intra-tumor H2O2 into highly toxic ·OH as a CDT. HMnO2 with large pores, pore volume, and surface area exhibited a high CDDP loading capacity (>0.6 g-1). Treatment with CDDP-loaded HMnO2 increased the intratumor Pt-DNA content, leading to the up-regulation of γ-H2Aχ and an increase in tumor tissue damage. The decreased GSH triggered by HMnO2 auto-degradation protected Mn2+-generated ·OH from scavenging to amplify oxidative stress and enhance the efficacy of CDT. The nanoenzymes with encapsulated chemotherapeutic agents deplete GSH and remodel the TME. Thus, tumor CDT/chemotherapy combination therapy is an effective therapeutic strategy.


Assuntos
Antineoplásicos , Cisplatino , Glutationa , Compostos de Manganês , Manganês , Óxidos , Glutationa/metabolismo , Cisplatino/farmacologia , Cisplatino/química , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/administração & dosagem , Manganês/química , Animais , Óxidos/química , Óxidos/farmacologia , Linhagem Celular Tumoral , Microambiente Tumoral/efeitos dos fármacos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Neoplasias/metabolismo , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia
3.
Sci Total Environ ; 939: 173558, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38823700

RESUMO

Center Pivot Irrigation system (CPIs) is widely used in newly exploited arable land in sandy lands. These sandy lands are currently stable because of climate change and ecological restoration efforts since the beginning of the 21st century in northern China. The exploitation of these fixed sandy lands to arable land with CPIs may affect the soil wind erosion, yet it remains unknown. The temporal changes of CPIs and its effect on wind erosion module were analyzed and modeled from 2000 to 2020 in Mu-Us sandy land using satellite images and Revised Wind Erosion Equation (RWEQ). The establishment of CPIs started from 2010, boomed in 2015 and peaked in 2020. They were mainly transformed from woodland, grassland, and barren land near rivers in east and southeast, and from cropland in inter-dunes in west and southwest of Mu-Us sandy land. The temporal and spatial pattern of CPIs well aligns with the land consolidation and requisition-compensation balance policies. In most of the Mu-Us sandy land, the annual erosion module is <25 t ha-1 a-1. Despite great variation, the annual, Winter and Spring erosion module of the Mu-Us sandy land or in Otog Qian and Yuyang, the CPIs concentrated counties, all decreased during 2000-2019. Although, wind erosion module in CPIs was lower than the surrounding area, it increased in 2019 given the same climate conditions as in 2010. Our results suggest 1) the establishment of CPIs in Mu-Us sandy land greatly depends on the local policy and natural endowment, and 2) although the set-up of CPIs showed no impact on the wind erosion with CPIs accounting for <1 % of Mu-Us sandy land, post-harvest of CPIs should be carefully concerned to prevent soil wind erosion.

4.
iScience ; 27(5): 109818, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38766356

RESUMO

Allergic asthma is a chronic non-communicable disease characterized by lung tissue inflammation. Current treatments can alleviate the clinical symptoms to some extent, but there is still no cure. Recently, the transplantation of mesenchymal stem cells (MSCs) has emerged as a potential approach for treating allergic asthma. Gingival-derived mesenchymal stem cells (GMSCs), a type of MSC recently studied, have shown significant therapeutic effects in various experimental models of autoimmune diseases. However, their application in allergic diseases has yet to be fully elucidated. In this study, using an OVA-induced allergic asthma model, we demonstrated that GMSCs decrease CD11b+CD11c+ proinflammatory dendritic cells (DCs), reduce Th2 cells differentiation, and thus effectively diminish eosinophils infiltration. We also identified that the core functional factor, hepatocyte growth factor (HGF) secreted by GMSCs, mediated its effects in relieving airway inflammation. Taken together, our findings indicate GMSCs as a potential therapy for allergic asthma and other related diseases.

5.
Adv Mater ; 36(24): e2313752, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38576272

RESUMO

Conventional conductive materials such as metals are crucial functional components of conductive systems in diverse electronic instruments. However, their severe intrinsic impedance mismatch with air dielectric causes strong reflection of incident electromagnetic waves, and the resulting low electromagnetic transmissivity typically interferes with surrounding electromagnetic signal communications in modern multifunction-integrated instruments. Herein, graphene glass fiber fabric (GGFF) that merges intrinsic electrical and electromagnetic properties of graphene with dielectric attributes and highly porous macrostructure of glass fiber fabric (GFF) is innovatively developed. Using a novel decoupling chemical vapor deposition growth strategy, high-quality and layer-limited graphene is prepared on noncatalytic nonmetallic GFF in a controlled manner; this is pivotal to realizing GGFF with the desired compatibility among high conductivity, low electromagnetic reflectivity, and high electromagnetic transmissivity. At the same sheet resistance over a wide range of values (250-3000 Ω·sq-1), the GGFF exhibits significantly lower electromagnetic reflectivity (by 0.42-0.51) and higher transmissivity (by 0.27-0.62) than those of its metal-based conductive counterpart (CuGFF). The material design strategy reported herein provides a constructive solution to eliminate the incompatibility between electrical conductivity and electromagnetic transmissivity faced by conventional conductive materials, spotlighting the applicability of GGFF in electric heating scenarios in radar, antenna, and stealth systems.

6.
Redox Biol ; 69: 103008, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38142586

RESUMO

Focal iron overload is frequently observed in patients with rheumatoid arthritis (RA), yet its functional significance remains elusive. Herein, we report that iron deposition in lesion aggravates arthritis by inducing macrophage ferroptosis. We show that excessive iron in synovial fluid positively correlates with RA disease severity as does lipid hyperoxidation of focal monocyte/macrophages. Further study reveals high susceptibility to iron induced ferroptosis of the anti-inflammatory macrophages M2, while pro-inflammatory M1 are less affected. Distinct glutathione peroxidase 4 (GPX4) degradation depending on p62/SQSTM1 in the two cell types make great contribution mechanically. Of note, ferroptosis inhibitor liproxstatin-1 (LPX-1) can alleviate the progression of K/BxN serum-transfer induced arthritis (STIA) mice accompanied with increasing M2 macrophages proportion. We thus propose that the heterogeneous ferroptosis susceptibility of macrophage subtypes as well as consequent inflammation and immune disorders are potential biomarkers and therapeutic targets in RA.


Assuntos
Artrite Reumatoide , Ferroptose , Sobrecarga de Ferro , Humanos , Camundongos , Animais , Artrite Reumatoide/metabolismo , Macrófagos/metabolismo , Sobrecarga de Ferro/patologia , Ferro/metabolismo
7.
Front Bioeng Biotechnol ; 11: 1258613, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38344075

RESUMO

To compare the muscular characteristics of "hit" and "miss" actions in roundhouse kicks among taekwondo athletes, and explore the similarities, differences, and implications for training, motion tests were conducted on ten taekwondo athletes using Noraxon32 and VICON. The results showed no significant differences (p > 0.05) in integrated electromyography (EMG) during the initiation and kicking phases between "miss" and "hit" actions. However, during the retraction phase, significant differences (p < 0.05) were observed in the left rectus femoris, left peroneus longus, right biceps femoris, right semitendinosus, and right tibialis anterior muscles. The tibialis anterior muscle of the swinging leg was activated first in the "hit" action, while the biceps femoris was activated first in the "miss" action. The supporting-side rectus femoris was activated first in the "hit" action, whereas it was the biceps femoris in the "miss" action. In both techniques, the gluteus maximus was the last muscle to be activated. The "miss" action had a longer cycle, and the duration of muscle work was longer than in the "hit" action. During the retraction phase of the front leg roundhouse kick, the muscles worked more than during the kicking phase, with the erector spinae and tibialis anterior being the core force-producing muscles in both techniques, characterized by high EMG values and long activation times. In the "miss" action, the thigh muscles drove the calf muscles, while the "hit" action exhibited the opposite pattern. "Hit" actions had a faster cycle compared to "miss," with greater force generation in "miss." The hip flexors and knee extensors of the kicking leg were the core force-producing muscles during the kicking process, determining the effectiveness and completion of the action.

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