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1.
J Cell Mol Med ; 28(7): e18240, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38509741

ABSTRACT

Growing evidence supports the analgesic efficacy of electroacupuncture (EA) in managing chronic neuropathic pain (NP) in both patients and NP models induced by peripheral nerve injury. However, the underlying mechanisms remain incompletely understood. Ferroptosis, a novel form of programmed cell death, has been found to be activated during NP development, while EA has shown potential in promoting neurological recovery following acute cerebral injury by targeting ferroptosis. In this study, to investigate the detailed mechanism underlying EA intervention on NP, male Sprague-Dawley rats with chronic constriction injury (CCI)-induced NP model received EA treatment at acupoints ST36 and GV20 for 14 days. Results demonstrated that EA effectively attenuated CCI-induced pain hypersensitivity and mitigated neuron damage and loss in the spinal cord of NP rats. Moreover, EA reversed the oxidative stress-mediated spinal ferroptosis phenotype by upregulating reduced expression of xCT, glutathione peroxidase 4 (GPX4), ferritin heavy chain (FTH1) and superoxide dismutase (SOD) levels, and downregulating increased expression of acyl-CoA synthetase long-chain family member 4 (ACSL4), malondialdehyde levels and iron overload. Furthermore, EA increased the immunofluorescence co-staining of GPX4 in neurons cells of the spinal cord of CCI rats. Mechanistic analysis unveiled that the inhibition of antioxidant pathway of Nrf2 signalling via its specific inhibitor, ML385, significantly countered EA's protective effect against neuronal ferroptosis in NP rats while marginally diminishing its analgesic effect. These findings suggest that EA treatment at acupoints ST36 and GV20 may protect against NP by inhibiting neuronal ferroptosis in the spinal cord, partially through the activation of Nrf2 signalling.


Subject(s)
Electroacupuncture , Ferroptosis , Neuralgia , Humans , Rats , Male , Animals , Rats, Sprague-Dawley , Electroacupuncture/methods , NF-E2-Related Factor 2/metabolism , Neuralgia/metabolism , Neurons/metabolism , Spinal Cord/metabolism , Analgesics
2.
ACS Cent Sci ; 9(10): 1905-1912, 2023 Oct 25.
Article in English | MEDLINE | ID: mdl-37901173

ABSTRACT

Acetate derived from electrocatalytic CO2 reduction represents a potential low-carbon synthesis approach. However, the CO2-to-acetate activity and selectivity are largely inhibited by the low surface coverage of in situ generated *CO, as well as the inefficient ethenone intermediate formation due to the side reaction between CO2 and alkaline electrolytes. Tuning catalyst microenvironments by chemical modification of the catalyst surface is a potential strategy to enhance CO2 capture and increase local *CO concentrations, while it also increases the selectivity of side reduction products, such as methane or ethylene. To solve this challenge, herein, we developed a hydrophilic amine-tailed, dendrimer network with enhanced *CO intermediate coverage on Cu catalytic sites while at the same time retaining the in situ generated OH- as a high local pH environment that favors the ethenone intermediate toward acetate. The optimized amine-network coordinated Cu catalyst (G3-NH2/Cu) exhibits one of the highest CO2-to-acetate Faradaic efficiencies of 47.0% with a partial current density of 202 mA cm-2 at -0.97 V versus the reversible hydrogen electrode.

3.
Angew Chem Int Ed Engl ; 62(43): e202309319, 2023 Oct 23.
Article in English | MEDLINE | ID: mdl-37673793

ABSTRACT

Electroreduction of CO2 to multi-carbon (C2+ ) products is a promising approach for utilization of renewable energy, in which the interfacial water quantity is critical for both the C2+ product selectivity and the stability of Cu-based electrocatalytic sites. Functionalization of long-chain alkyl molecules on a catalyst surface can help to increase its stability, while it also tends to block the transport of water, thus inhibiting the C2+ product formation. Herein, we demonstrate the fine tuning of interfacial water by surface assembly of toluene on Cu nanosheets, allowing for sustained and enriched CO2 supply but retarded water transfer to catalytic surface. Compared to bare Cu with fast cathodic corrosion and long-chain alkyl-modified Cu with main CO product, the toluene assembly on Cu nanosheet surface enabled a high Faradaic efficiency of 78 % for C2+ and a partial current density of 1.81 A cm-2 . The toluene-modified Cu catalyst further exhibited highly stable CO2 -to-C2 H4 conversion of 400 h in a membrane-electrode-assembly electrolyzer, suggesting the attractive feature for both efficient C2+ selectivity and excellent stability.

4.
Nat Commun ; 14(1): 280, 2023 Jan 17.
Article in English | MEDLINE | ID: mdl-36650135

ABSTRACT

Self-reconstruction has been considered an efficient means to prepare efficient electrocatalysts in various energy transformation process for bond activation and breaking. However, developing nano-sized electrocatalysts through complete in-situ reconstruction with improved activity remains challenging. Herein, we report a bottom-up evolution route of electrochemically reducing Cs3Rh2I9 halide-perovskite clusters on N-doped carbon to prepare ultrafine Rh nanoparticles (~2.2 nm) with large lattice spacings and grain boundaries. Various in-situ and ex-situ characterizations including electrochemical quartz crystal microbalance experiments elucidate the Cs and I extraction and Rh reduction during the electrochemical reduction. These Rh nanoparticles from Cs3Rh2I9 clusters show significantly enhanced mass and area activity toward hydrogen evolution reaction in both alkaline and chlor-alkali electrolyte, superior to liquid-reduced Rh nanoparticles as well as bulk Cs3Rh2I9-derived Rh via top-down electro-reduction transformation. Theoretical calculations demonstrate water activation could be boosted on Cs3Rh2I9 clusters-derived Rh nanoparticles enriched with multiply sites, thus smoothing alkaline hydrogen evolution.

5.
Oncotarget ; 12(18): 1811-1820, 2021 Aug 31.
Article in English | MEDLINE | ID: mdl-34504653

ABSTRACT

The incidence of postoperative delirium (POD) after maxillofacial tumors radical surgery is relatively high. There are a number of evidences showing the relationship between hypertension and decreased cerebral blood flow, as well as the relationship between cerebral ischemia and postoperative cognitive impairment. However, the impact of hypertension in the process of POD and related mechanisms remain unclear. This study included 98 elderly patients who underwent maxillofacial tumors radical surgery in our hospital, from June 2020 to December 2020. We collected the general condition of patients and related research factors before surgery, and also collected related intraoperative factors. After that, we would follow up the patients for POD evaluation. The incidence of POD in the hypertension group was 41%, compared with 12% in the nonhypertension group (P < 0.05). The incidence of POD in the irregular medication group was 62%, compared with 26% in the regular medication group (P < 0.05). Both hypertension (OR = 2.45, 95% CI = 1.11-5.72) and irregular medication use (OR = 2.35, 95% CI = 0.87-5.69) were independent risk factors for POD after this type of surgery in elderly patients. Hypertension and medication use regularity are closely related to POD. This may be related to the delayed postoperative response caused by intraoperative cerebral ischemia.

6.
Chem Commun (Camb) ; 56(71): 10289-10292, 2020 Sep 14.
Article in English | MEDLINE | ID: mdl-32756688

ABSTRACT

To work against the volume expansion (∼300%) of SnO2 during lithiation, here a sub-micro sized, interconnected, and porous SnO2 cube with rationally designed reserved space (∼375%) is synthesized via an artful topochemistry route (CaSn(OH)6-CaSnO3-SnO2). Owing to its microstructure, this novel material harvests enhanced lithium-storage performance.

7.
Oncotarget ; 7(52): 86103-86116, 2016 Dec 27.
Article in English | MEDLINE | ID: mdl-27861141

ABSTRACT

Ectopic glucose-6-phosphate dehydrogenase (G6PD) expression may contribute to tumorigenesis in cervical cancer associated with high-risk human papillomavirus (HR-HPV 16 and 18) infections. Here, we demonstrate that microRNA-1 (miR-1) in association with AGO proteins targets G6PD in HR-HPV-infected human cervical cancer cells. miR-1 inhibited expression of a reporter construct containing a putative G6PD 3'-UTR seed region and suppressed endogenous G6PD expression. Down-regulation of miR-1 increased G6PD expression in cervical cancer cells. Regression analysis revealed that miR-1 levels correlate negatively with the clinicopathologic features in HR-HPV 16/18-infected cervical cancer patients. miR-1 overexpression inhibited proliferation and promoted apoptosis in cervical cancer cells and reduced xenograft tumor growth in nude mice. Conversely, sponge-mediated miR-1 knockdown markedly increased viability and reduced apoptosis in cervical cancer cells and supported neoplasm growth. Restoration of G6PD expression partially reversed the effects of miR-1 overexpression both in vitro and in vivo. In addition, co-transfection of G6PD siRNA and miR-1 sponge partially reversed miR-1 sponge-induced reductions in cell viability and neoplasm growth. These results suggest that miR-1 suppresses the development and progression of HR-HPV 16/18-infected cervical cancer by targeting G6PD and may be a promising novel therapeutic candidate.


Subject(s)
Glucosephosphate Dehydrogenase/genetics , Human papillomavirus 16/isolation & purification , Human papillomavirus 18/isolation & purification , MicroRNAs/physiology , Uterine Cervical Neoplasms/prevention & control , Animals , Cell Line, Tumor , Disease Progression , Female , Humans , Mice , Mice, Inbred BALB C , Risk , Uterine Cervical Neoplasms/virology
8.
J Drug Target ; 18(5): 389-403, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20055559

ABSTRACT

To understand more about the influence of the types of interaction between drug and PEGylated PAMAM dendrimers on the in vitro and in vivo behavior of drug, methotrexate (MTX) was coupled to PEGylated or non-PEGylated generation 4 PAMAM (G4) through complexing drug within the dendritic architecture and covalently conjugated onto the surface of the dendrimer, respectively. PAMAM was first modified with PEG(5000) chains at three different degrees of substitution. The ability of PEGylated G4 complexing MTX was higher than that of non-PEGylated one. MTX-G4 and MTX-G4-PEG conjugates were synthesized via amide linkages. MTX was readily released from all complexes in isotonic solution, while the conjugates hardly released MTX in the same medium and keep stable in human plasma and the lysosomal medium. There were no obvious differences between complexes and free MTX in cytotoxicity against KB cell line, whereas the conjugates showed the relatively low activity. In vivo study in rodents found that the MTX-G4-PEG conjugate exhibited significantly prolonged blood residence time and the strongest antitumor effects, as compared with MTX-G4, the complexes and MTX. The results indicated that the covalent attachment of drug to PEGylated PAMAM could be more effective for targeted drug delivery.


Subject(s)
Dendrimers/administration & dosage , Drug Carriers , Polyethylene Glycols/chemistry , Animals , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Dendrimers/chemistry , Female , Hemolysis/drug effects , Humans , Magnetic Resonance Spectroscopy , Male , Methotrexate/administration & dosage , Methotrexate/pharmacokinetics , Methotrexate/pharmacology , Mice , Rats , Rats, Sprague-Dawley
9.
Yao Xue Xue Bao ; 44(1): 85-90, 2009 Jan.
Article in Chinese | MEDLINE | ID: mdl-19350828

ABSTRACT

Generation 4 polyamidoamine (PAMAM) dendrimer was PEGylated with polyethylene glycol (PEG) at an average molecular weight 5 000 via amide bond. PAMAM and PEGylated PAMAM (PAMAM-PEG) dendrimer were used as drug nanocarriers. Methotrexate (MTX), an antineoplastic agent, was selected as a model drug. PAMAM/MTX and PAMAM-PEG/MTX complexes were prepared. The pharmacokinetic characters and anti-tumor activity of the PAMAM-PEG/MTX complex were studied as compared with MTX injection and PAMAM/MTX complex by intravenous injection in rats and S180 tumor bearing mice, separately. The plasma samples from normal rats were analyzed by HPLC method, and concentration-time data were analyzed using a non-compartmental analysis. Their anti-tumor effects in vivo were evaluated against S180 solid tumors in mice by measuring average tumor weight and calculating the inhibitory rate of tumor on day 17 after successive injections. The results showed that both plasma half-life and mean retention time (MRT) of the complexes were longer than that of MTX injection (P<0.01), while the area under the plasma concentration vs time curve (AUC) of PAMAM-PEG/MTX was the largest as compared with that of free drug and PAMAM/MTX complex (P<0.01). The inhibitory rate of tumor of PAMAM-PEG/MTX complex enhanced 2.1 and 1.8 times over that of free drug and PAMAM/MTX complex, respectively, indicating that PAMAM-PEG/MTX exhibited the highest antitumor activity. In summary, PEGylated PAMAM could be useful as a potential drug delivery carrier.


Subject(s)
Antimetabolites, Antineoplastic/pharmacokinetics , Dendrimers/pharmacokinetics , Drug Carriers , Methotrexate/pharmacokinetics , Nylons/pharmacokinetics , Sarcoma 180/pathology , Animals , Antimetabolites, Antineoplastic/blood , Antimetabolites, Antineoplastic/pharmacology , Area Under Curve , Cell Line, Tumor , Dendrimers/chemical synthesis , Female , Male , Methotrexate/blood , Methotrexate/pharmacology , Mice , Neoplasm Transplantation , Nylons/chemical synthesis , Polyethylene Glycols/chemistry , Random Allocation , Rats , Rats, Sprague-Dawley , Tumor Burden/drug effects
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