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1.
Adv Mater ; : e2407719, 2024 Aug 13.
Article in English | MEDLINE | ID: mdl-39136048

ABSTRACT

Flexible and high-performance lithium-ion batteries (LIBs) encounter challenges due to the inherent trade-offs in conventional electrode designs, particularly concerning mechanical flexibility and high energy density. Here, a novel percolative metal microweb-based electrode, fabricated via electrohydrodynamic processes, yielding a three-dimensional (3D) network structure with exceptional electrical properties and mechanical durability is introduced. This lightweight electrode design addresses the need for improved energy density by reducing the weight of the current collector, which typically accounts for more than 10% of the battery's weight. The 3D architecture of the electrode enhances the contact area with the electrolyte, thereby minimizing polarization voltage and improving lithium-ion diffusion. Furthermore, the low coating thickness-to-weight ratio promotes electron transfer and mitigates capacity fade at high current densities. The microweb-based full cell exhibits energy and power densities of 110 and 1,048 W kg⁻¹ at 10 C, respectively, which are the highest reported values among LIBs utilizing similar materials. The design of the electrode proposed in this study is expected to significantly contribute to the development of wearable and flexible electronics.

2.
Eur J Pharmacol ; 643(1): 21-8, 2010 Sep 15.
Article in English | MEDLINE | ID: mdl-20599928

ABSTRACT

Caffeic acid phenethyl ester (CAPE) is an active component of propolis from honeybee. We investigated potential molecular mechanisms underlying CAPE-mediated nuclear factor kappa beta (NFkappaB) inhibition and analyzed structure of CAPE for its biological effect. CAPE attenuated expression of NFkappaB dependent luciferase stimulated with TNF-alpha or LPS and suppressed LPS-mediated induction of iNOS, a target gene product of NFkappaB. In HCT116 cells, CAPE interfered with TNF-alpha dependent IkappaBalpha degradation and subsequent nuclear accumulation of p65, which occurred by direct inhibition of inhibitory protein kappaB kinase (IKK). CAPE increased the expression of Nrf2-dependent luciferase and heme oxygenase-1, a target gene of Nrf2, and elevated the nuclear level of Nrf2 protein, indicating that CAPE activated the Nrf2 pathway. In HCT116 cells with stable expression of Nrf2 shRNA, CAPE elicited a reduced inhibitory effect on TNF-alpha-activated NFsmall ka, CyrillicB compared to scramble RNA expressing control cells. On the other hand, the NFkappaB inhibitory effect of CAPE was diminished by removal or modification of the Michael reaction acceptor, catechol or phenethyl moiety in CAPE. These data suggest that CAPE inhibits TNF-alpha-dependent NFkappaB activation via direct inhibition of IKK as well as activation of Nrf2 pathway, in which the functional groups in CAPE may be involved.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Caffeic Acids/pharmacology , I-kappa B Kinase/antagonists & inhibitors , NF-E2-Related Factor 2/metabolism , NF-kappa B/antagonists & inhibitors , Phenylethyl Alcohol/analogs & derivatives , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Caffeic Acids/chemistry , Cell Culture Techniques , Cell Line, Tumor , Cell Nucleus/drug effects , Cell Nucleus/enzymology , Cell Nucleus/metabolism , Cytosol/drug effects , Cytosol/enzymology , Cytosol/metabolism , Genes, Reporter , Humans , Immunoblotting , Lipopolysaccharides/pharmacology , Luciferases/genetics , Macrophages/drug effects , Macrophages/enzymology , Macrophages/metabolism , Mice , Molecular Structure , NF-E2-Related Factor 2/antagonists & inhibitors , NF-E2-Related Factor 2/genetics , Phenylethyl Alcohol/chemistry , Phenylethyl Alcohol/pharmacology , Plasmids , Recombinant Proteins/pharmacology , Reverse Transcriptase Polymerase Chain Reaction , Structure-Activity Relationship , Transfection , Tumor Necrosis Factor-alpha/pharmacology
3.
J Nutr Biochem ; 21(9): 809-17, 2010 Sep.
Article in English | MEDLINE | ID: mdl-19740641

ABSTRACT

Caffeic acid phenethyl ester (CAPE) is an active component of propolis from honeybee. We investigated a potential molecular mechanism underlying a CAPE-mediated protective effect against ischemia/reperfusion (I/R) injury and analyzed the structure contributing to the CAPE effect. CAPE induced hypoxia-inducible factor-1 (HIF-1) alpha protein, concomitantly transactivating the HIF-1 target genes vascular endothelial growth factor and heme oxygenase-1, which play a protective role in I/R injury. CAPE delayed the degradation of HIF-1alpha protein in cells, which occurred by inhibition of HIF prolyl hydroxylase (HPH), the key enzyme for von Hippel-Lindau-dependent HIF-1alpha degradation. CAPE inhibition of HPH and induction of HIF-1alpha protein were neutralized by an elevated dose of iron. The catechol moiety, a chelating group, is essential for HPH inhibition, while hydrogenation of the double bond (-C=C-) in the Michael reaction acceptor markedly reduced potency. Removal of the phenethyl moiety of CAPE (substitution with the methyl moiety) severely deteriorated its inhibitory activity for HPH. Our data suggest that a beneficial effect of CAPE on I/R injury may be ascribed to the activation of HIF-1 pathway via inhibition of HPH and reveal that the chelating moiety of CAPE acted as a pharmacophore while the double bond and phenethyl moiety assisted in inhibiting HPH.


Subject(s)
Caffeic Acids/pharmacology , Phenylethyl Alcohol/analogs & derivatives , Procollagen-Proline Dioxygenase/antagonists & inhibitors , Animals , Cells, Cultured , Enzyme Inhibitors/pharmacology , HEK293 Cells , Heme Oxygenase-1/metabolism , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Phenylethyl Alcohol/pharmacology , Reperfusion Injury/prevention & control , Structure-Activity Relationship , Transfection , Tumor Cells, Cultured , Vascular Endothelial Growth Factor A/metabolism
4.
Toxicol Appl Pharmacol ; 235(3): 261-7, 2009 Mar 15.
Article in English | MEDLINE | ID: mdl-19263519

ABSTRACT

Manganese (II), a transition metal, causes pulmonary inflammation upon environmental or occupational inhalation in excess. We investigated a potential molecular mechanism underlying manganese-induced pulmonary inflammation. Manganese (II) delayed HIF-1alpha protein disappearance, which occurred by inhibiting HIF-prolyl hydroxylase (HPH), the key enzyme for HIF-1alpha hydroxylation and subsequent von Hippel-Lindau(VHL)-dependent HIF-1alpha degradation. HPH inhibition by manganese (II) was neutralized significantly by elevated dose of iron. Consistent with this, the induction of cellular HIF-1alpha protein by manganese (II) was abolished by pretreatment with iron. Manganese (II) induced the HIF-1 target gene involved in pulmonary inflammation, vascular endothelial growth factor (VEGF), in lung carcinoma cell lines.The induction of VEGF was dependent on HIF-1. Manganese-induced VEGF promoted tube formation of HUVEC. Taken together, these data suggest that HIF-1 may be a potential mediator of manganese-induced pulmonary inflammation.


Subject(s)
Chlorides/toxicity , Hypoxia-Inducible Factor 1, alpha Subunit/antagonists & inhibitors , Inflammation Mediators/toxicity , Pneumonia/chemically induced , Pneumonia/enzymology , Procollagen-Proline Dioxygenase/antagonists & inhibitors , Cell Hypoxia/drug effects , Cell Hypoxia/physiology , Cell Line, Tumor , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Manganese Compounds , Pneumonia/pathology , Procollagen-Proline Dioxygenase/metabolism , Vascular Endothelial Growth Factor A/metabolism
5.
J Pharm Sci ; 98(1): 159-68, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18399548

ABSTRACT

To evaluate N,N'-bis(5-aminosalicyl)-L-cystine (5-ASA-Cys) as a potential colon-specific 5-aminosalicylic acid prodrug with dual therapeutic effects in experimental colitis, the pharmacokinetics and therapeutic activity were investigated after oral administration of 5-ASA-Cys and amelioration of experimental colitis was compared after rectal administration of 5-aminosalicylic acid (5-ASA) and/or cysteine. In addition, the gluthathione (GSH) level in the inflamed colonic tissue was examined after administration of cysteine or 5-ASA-Cys. Oral administration of 5-ASA-Cys delivered much greater amount of 5-ASA to the large intestine and excreted lower amount of 5-ASA via urine than that of free 5-ASA. Oral administration of 5-ASA-Cys ameliorated experimental colitis of rats induced by TNBS, which was more effective than that of sulfasalazine. Although cysteine administered rectally was not significantly effective, intracolonic treatment with both 5-ASA and cysteine showed a synergic effect in alleviating the rat colitis. Furthermore, not only 5-ASA-Cys administered orally but also cysteine administered rectally increased the glutathione level in the inflamed colonic tissue. Taken together, these results suggest that 5-ASA-Cys is a potential colon specific 5-ASA prodrug with dual therapeutic effects on experimental colitis and cysteine modulation of the glutathione level may be relevant to the dual effects of the prodrug.


Subject(s)
Aminosalicylic Acids/administration & dosage , Colitis/drug therapy , Colon/drug effects , Cystine/analogs & derivatives , Prodrugs/administration & dosage , Aminosalicylic Acids/chemistry , Animals , Colitis/metabolism , Colon/metabolism , Cystine/administration & dosage , Cystine/chemistry , Male , Prodrugs/chemistry , Rats , Rats, Sprague-Dawley
6.
Drug Deliv ; 15(1): 37-42, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18197522

ABSTRACT

N,N(')-bis(5-aminosalicyl)-L-cystine (5-ASA-Cys) was prepared by a simple synthetic route. 5-ASA-Cys was not degraded in pH 1.2 and 6.8 buffer solutions, and in the homogenates of the upper intestine. In marked contrast, 5-ASA-Cys was deconjugated extensively to liberate 5-ASA in the cecal contents. Upon oral administration of 5-ASA-Cys to rats, the plasma concentration of 5-ASA-Cys was extremely low and the urinary recovery of 5-ASA-Cys was approximately 10% of the dose. These results suggest that 5-ASA-Cys administered orally is delivered efficiently to the large intestine followed by deconjugation to liberate 5-ASA and cystine.


Subject(s)
Aminosalicylic Acids/pharmacokinetics , Anti-Inflammatory Agents/pharmacokinetics , Colon/metabolism , Cystine/analogs & derivatives , Gastrointestinal Agents/pharmacokinetics , Intestinal Absorption , Prodrugs/chemical synthesis , Administration, Oral , Aminosalicylic Acids/administration & dosage , Aminosalicylic Acids/chemical synthesis , Animals , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/chemical synthesis , Biotransformation , Cecum/metabolism , Cystine/administration & dosage , Cystine/chemical synthesis , Cystine/pharmacokinetics , Drug Stability , Gastric Mucosa/metabolism , Gastrointestinal Agents/administration & dosage , Gastrointestinal Agents/chemical synthesis , Hippurates/pharmacokinetics , Hydrogen-Ion Concentration , Intestine, Small/metabolism , Male , Prodrugs/administration & dosage , Prodrugs/metabolism , Rats , Rats, Sprague-Dawley
7.
Mol Pharmacol ; 71(6): 1676-84, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17377063

ABSTRACT

We investigated a molecular mechanism underlying quercetin-mediated amelioration of colonic mucosal injury and analyzed chemical structure contributing to the quercetin's effect. Quercetin up-regulated vascular endothelial growth factor (VEGF), an ulcer healing factor, not only in colon epithelial cell lines but also in the inflamed colonic tissue. VEGF derived from quercetin-treated colon epithelial cells promoted tube formation. The VEGF induction was dependent on quercetin-mediated hypoxia-inducible factor-1 (HIF-1) activation. Quercetin delayed HIF-1alpha protein disappearance, which occurred by inhibiting HIF-prolyl hydroxylase (HPH), the key enzyme for HIF-1alpha hydroxylation and subsequent von Hippel Lindau-dependent HIF-1alpha degradation. HPH inhibition by quercetin was neutralized significantly by an elevated dose of iron. Consistent with this, cellular induction of HIF-1alpha by quercetin was abolished by pretreatment with iron. Two iron-chelating moieties in quercetin, -OH at position 3 of the C ring and/or -OH at positions 3' and 4' of the B ring, enabled the flavonoid to inhibit HPH and subsequently induce HIF-1alpha. Our data suggest that the clinical effect of quercetin may be partly attributed to the activation of an angiogenic pathway HIF-1-VEGF via inhibiting HPH and the chelating moieties of quercetin were required for inhibiting HPH.


Subject(s)
Epithelial Cells/drug effects , Hypoxia-Inducible Factor 1/physiology , Procollagen-Proline Dioxygenase/antagonists & inhibitors , Quercetin/pharmacology , Vascular Endothelial Growth Factor A/metabolism , Cells, Cultured , Chelating Agents/metabolism , Colon/cytology , Epithelial Cells/metabolism , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/biosynthesis , Procollagen-Proline Dioxygenase/metabolism , Up-Regulation , Vascular Endothelial Growth Factor A/biosynthesis , Vascular Endothelial Growth Factor A/drug effects
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