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1.
Am J Physiol Renal Physiol ; 322(4): F437-F448, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35073210

RESUMO

Calcineurin inhibitors such as cyclosporin A (CsA) have been widely used to improve graft survival following solid-organ transplantation. However, the clinical use of CsA is often limited by its nephrotoxicity. The present study tested the hypothesis that activation of the (pro)renin receptor (PRR) contributes to CsA-induced nephropathy by activating the renin-angiotensin system (RAS). Renal injury in male Sprague-Dawley rats was induced by a low-salt diet combined with CsA as evidenced by elevated plasma creatinine and blood urea nitrogen levels, decreased creatinine clearance and induced renal inflammation, apoptosis and interstitial fibrosis, and elevated urinary N-acetyl-ß-d-glucosaminidase activity and urinary kidney injury molecule-1 content. Each index of renal injury was attenuated following 2 wk of treatment with the PRR decoy inhibitor PRO20. Although CsA-treated rats with kidney injury displayed increased renal soluble (s)PRR abundance, plasma sPRR, renin activity, angiotensin II, and heightened urinary total prorenin/renin content, RAS activation was attenuated by PRO20. Exposure of cultured human renal proximal tubular HK-2 cells to CsA induced expression of fibronectin and sPRR production, but the fibrotic response was attenuated by PRO20 and siRNA-mediated PRR knockdown. These findings support the hypothesis that activation of PRR contributes to CsA-induced nephropathy by activating the RAS in rats. Of importance, we provide strong proof of concept that targeting PRR offers a novel therapeutic strategy to limit nephrotoxic effects of immunosuppressant drugs.NEW & NOTEWORTHY The present study reports, for the first time, that activation of the (pro)renin receptor drives the renin-angiotensin system to induce renal injury during cyclosporin A administration. More importantly, our study has identified that antagonism with PRO20 offers a novel intervention in the management of side effects of cyclosporin A.


Assuntos
Nefropatias , Renina , Animais , Creatinina/metabolismo , Ciclosporina/toxicidade , Feminino , Humanos , Rim/metabolismo , Nefropatias/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Receptores de Superfície Celular/metabolismo , Renina/metabolismo , Sistema Renina-Angiotensina
2.
J Org Chem ; 87(24): 16937-16940, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36455299

RESUMO

We present here a rhodium-catalyzed reaction between N-acyl pyridazinones and diazoacetates, leading to pyridazine derivatives in good yield under mild reaction conditions. This whole sequence probably proceeds through a carbene insertion into a C═O bond and an unprecedented 1,4-N-to-O acyl rearrangement reaction.

3.
Clin Sci (Lond) ; 135(6): 793-810, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33625485

RESUMO

Until now, renin-angiotensin system (RAS) hyperactivity was largely thought to result from angiotensin II (Ang II)-dependent stimulation of the Ang II type 1 receptor (AT1R). Here we assessed the role of soluble (pro)renin receptor (sPRR), a product of site-1 protease-mediated cleavage of (pro)renin receptor (PRR), as a possible ligand of the AT1R in mediating: (i) endothelial cell dysfunction in vitro and (ii) arterial dysfunction in mice with diet-induced obesity. Primary human umbilical vein endothelial cells (HUVECs) treated with a recombinant histidine-tagged sPRR (sPRR-His) exhibited IκBα degradation concurrent with NF-κB p65 activation. These responses were secondary to sPRR-His evoked elevations in Nox4-derived H2O2 production that resulted in inflammation, apoptosis and reduced NO production. Each of these sPRR-His-evoked responses was attenuated by AT1R inhibition using Losartan (Los) but not ACE inhibition using captopril (Cap). Further mechanistic exploration revealed that sPRR-His activated AT1R downstream Gq signaling pathway. Immunoprecipitation coupled with autoradiography experiments and radioactive ligand competitive binding assays indicate sPRR directly interacts with AT1R via Lysine199 and Asparagine295. Important translational relevance was provided by findings from obese C57/BL6 mice that sPRR-His evoked endothelial dysfunction was sensitive to Los. Besides, sPRR-His elevated blood pressure in obese C57/BL6 mice, an effect that was reversed by concurrent treatment with Los but not Cap. Collectively, we provide solid evidence that the AT1R mediates the functions of sPRR during obesity-related hypertension. Inhibiting sPRR signaling should be considered further as a potential therapeutic intervention in the treatment and prevention of cardiovascular disorders involving elevated blood pressure.


Assuntos
Hipertensão/fisiopatologia , Receptor Tipo 1 de Angiotensina/efeitos dos fármacos , Receptores de Superfície Celular/metabolismo , Animais , Anti-Hipertensivos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Captopril/farmacologia , Dieta Hiperlipídica/efeitos adversos , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio , Losartan/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade , Sistema Renina-Angiotensina/efeitos dos fármacos , Receptor de Pró-Renina
4.
Am J Physiol Renal Physiol ; 319(5): F941-F953, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32865015

RESUMO

Tubulointerstitial fibrosis has been regarded as a critical event in the pathogenesis of chronic kidney disease. The soluble form of (pro)renin receptor (sPRR), generated by site-1 protease (S1P) cleavage of full-length PRR, can be detected in biological fluid and elevated under certain pathological conditions. The present study was designed to evaluate the potential role of sPRR in the regulation of the fibrotic response in a cultured human renal proximal tubular cell line (HK-2 cells) in the setting of transforming growth factor (TGF)-ß or sPRR-His treatment. The TGF-ß-induced fibrotic response of HK-2 cells was indicated by upregulation of fibronectin (FN) expression; meanwhile, TGF-ß could also induce the generation of sPRR, due to enhanced cleavage of full-length PRR. To explore the role of sPRR in the fibrotic response of HK-2 cells, we blocked the production of sPRR with a the S1P inhibitor PF429242 and found that PF429242 remarkably suppressed TGF-ß-induced sPRR generation and FN expression in HK-2 cells. Administration of sPRR-His restored the PF429242-attenuated FN expression in HK-2 cells, indicating that sPRR could promote the TGF-ß-induced fibrotic response. Furthermore, sPRR-His alone also increased the abundance of FN in HK-2 cells. These data suggested that sPRR was sufficient and necessary for the TGF-ß-induced fibrotic response of HK-2 cells. Mechanistically, sPRR activated the AKT and ß-catenin pathway in HK-2 cells, and blockade of the AKT or ß-catenin pathway significantly abrogated sPRR-induced FN and Snail expression. Taking together, sPRR promoted the fibrotic response of HK-2 cells by activating Akt/ß-catenin/Snail signaling, and it may serve as a potential therapeutic target in renal fibrosis.


Assuntos
Células Epiteliais/metabolismo , Túbulos Renais Proximais/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , beta Catenina/metabolismo , Humanos , Rim/metabolismo , Receptores de Superfície Celular/metabolismo , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/patologia , Transdução de Sinais/fisiologia , Regulação para Cima/fisiologia
5.
Am J Physiol Renal Physiol ; 316(3): F530-F538, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30379098

RESUMO

The (pro)renin receptor (PRR) is a new component of the renin-angiotensin-aldosterone system (RAAS) and regulates renin activity. The objective of the present study was to test potential roles of the renal PRR and intrarenal RAAS in the physiological status of late pregnancy. Late pregnant Sprague-Dawley rats were studied 19-21 days after sperm was observed in vaginal smears. Experiments were performed using age-matched virgin rats and late pregnant rats treated with the specific PRR inhibitor PRO20 (700 µg·kg-1·day-1 sc for 14 days, 3 times/day for every 8 h) or vehicle. The indices of RAAS, including PRR, renin, angiotensin II, and aldosterone levels, were examined by immunoblotting, qRT-PCR, or ELISA. Further analyses of renal epithelial sodium channel (ENaC) expression, sodium-water retention, and plasma volume were performed. We first present evidence for the activation of intrarenal RAAS in late pregnant rats, including increases in urinary renin activity, active and total renin content, and prorenin content, angiotensin II and aldosterone excretion, in parallel with increased renal PRR expression and urinary soluble PRR excretion. Functional evidence demonstrated that PRR antagonism with PRO20 effectively suppressed the indices of intrarenal RAAS in late pregnant rats. In addition, our results revealed that renal α-ENaC expression, sodium-water retention, and plasma volume were elevated during late pregnancy, which were all attenuated by PRO20. In summary, the present study examined the renal mechanism of sodium-water retention and plasma volume expansion in late pregnant rats and identified a novel role of PRR in regulation of intrarenal RAAS and α-ENaC and thus sodium and fluid retention associated with pregnancy.


Assuntos
Canais Epiteliais de Sódio/metabolismo , Rim/metabolismo , Receptores de Superfície Celular/metabolismo , Sistema Renina-Angiotensina/fisiologia , Desequilíbrio Hidroeletrolítico/metabolismo , Aldosterona/metabolismo , Angiotensina II/metabolismo , Animais , Pressão Sanguínea/efeitos dos fármacos , Canais Epiteliais de Sódio/genética , Feminino , Rim/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Gravidez , Ratos , Ratos Sprague-Dawley , Receptores de Superfície Celular/genética , Renina/farmacologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Sódio/metabolismo , Água/metabolismo , Receptor de Pró-Renina
6.
Proc Natl Acad Sci U S A ; 113(13): E1898-906, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-26984496

RESUMO

The extracellular domain of the (pro)renin receptor (PRR) is cleaved to produce a soluble (pro)renin receptor (sPRR) that is detected in biological fluid and elevated under certain pathological conditions. The present study was performed to define the antidiuretic action of sPRR and its potential interaction with liver X receptors (LXRs), which are known regulators of urine-concentrating capability. Water deprivation consistently elevated urinary sPRR excretion in mice and humans. A template-based algorithm for protein-protein interaction predicted the interaction between sPRR and frizzled-8 (FZD8), which subsequently was confirmed by coimmunoprecipitation. A recombinant histidine-tagged sPRR (sPRR-His) in the nanomolar range induced a remarkable increase in the abundance of renal aquaporin 2 (AQP2) protein in primary rat inner medullary collecting duct cells. The AQP2 up-regulation relied on sequential activation of FZD8-dependent ß-catenin signaling and cAMP-PKA pathways. Inhibition of FZD8 or tankyrase in rats induced polyuria, polydipsia, and hyperosmotic urine. Administration of sPRR-His alleviated the symptoms of diabetes insipidus induced in mice by vasopressin 2 receptor antagonism. Administration of the LXR agonist TO901317 to C57/BL6 mice induced polyuria and suppressed renal AQP2 expression associated with reduced renal PRR expression and urinary sPRR excretion. Administration of sPRR-His reversed most of the effects of TO901317. In cultured collecting duct cells, TO901317 suppressed PRR protein expression, sPRR release, and PRR transcriptional activity. Overall we demonstrate, for the first time to our knowledge, that sPRR exerts antidiuretic action via FZD8-dependent stimulation of AQP2 expression and that inhibition of this pathway contributes to the pathogenesis of diabetes insipidus induced by LXR agonism.


Assuntos
Diabetes Insípido/tratamento farmacológico , Receptores Nucleares Órfãos/metabolismo , Receptores de Superfície Celular/metabolismo , Urina/química , beta Catenina/metabolismo , Animais , Aquaporina 2/metabolismo , Diabetes Insípido/urina , Hidrocarbonetos Fluorados/farmacologia , Receptores X do Fígado , Masculino , Camundongos Endogâmicos C57BL , Receptores Nucleares Órfãos/agonistas , Osmose , Ratos Sprague-Dawley , Receptores de Superfície Celular/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Solubilidade , Sulfonamidas/farmacologia , Urina/fisiologia , Via de Sinalização Wnt , Receptor de Pró-Renina
7.
Am J Physiol Renal Physiol ; 315(6): F1759-F1768, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29846109

RESUMO

Proteinuria is not only a common feature of chronic kidney diseases (CKD) but also an independent risk factor promoting CKD progression to end-stage renal failure. However, the underlying molecular mechanisms for protein overload-induced renal injury remain elusive. The present study examined the role of (pro)renin receptor (PRR) in pathogenesis of albumin overload (AO)-induced nephropathy and activation of the intrarenal renin-angiotensin system (RAS) in rats. Wistar rats underwent unilateral nephrectomy and were treated for 7 wk with vehicle, bovine serum albumin (5 g·kg-1·day-1 via a single ip injection), alone or in conjunction with the PRR decoy inhibitor PRO20 (500 µg·kg-1·day-1 via 3 sc injections). The AO rat model exhibited severe proteinuria, tubular necrosis, and interstitial fibrosis, oxidative stress, and inflammation, accompanied by elevated urinary N-acetyl-ß-d-glucosaminidase activity and urinary ß2-microglobulin secretion, all of which were significantly attenuated by PRO20. Urinary and renal levels of renin, angiotensinogen, and ANG II were elevated by AO and suppressed by PRO20, contrasting to largely unaltered plasma levels of the RAS parameters. The AO model also showed increased renal expression of full-length PRR and soluble PRR (sPRR) and urinary excretion of sPRR. Taken together, we conclude that PRR antagonism with PRO20 alleviates AO-induced nephropathy via inhibition of intrarenal RAS.


Assuntos
Nefropatias/metabolismo , Rim/metabolismo , Receptores de Superfície Celular/metabolismo , Sistema Renina-Angiotensina , Soroalbumina Bovina , Animais , Modelos Animais de Doenças , Fibrose , Mediadores da Inflamação/metabolismo , Rim/efeitos dos fármacos , Rim/fisiopatologia , Nefropatias/induzido quimicamente , Nefropatias/fisiopatologia , Nefropatias/prevenção & controle , Masculino , Nefrectomia , Estresse Oxidativo , Fragmentos de Peptídeos/farmacologia , Proteinúria/induzido quimicamente , Proteinúria/metabolismo , Proteinúria/fisiopatologia , Proteinúria/prevenção & controle , Ratos Wistar , Receptores de Superfície Celular/antagonistas & inibidores , Receptores de Superfície Celular/genética , Renina/farmacologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , ATPases Vacuolares Próton-Translocadoras , Receptor de Pró-Renina
8.
Langmuir ; 34(51): 15812-15819, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30485113

RESUMO

In this study, spiropyran (SP)-containing fluorinated polyacrylate (F-PA-SP) latex was prepared by emulsion polymerization using fluorinated and SP-based acrylic monomers as raw materials. Fourier transform infrared and 1H NMR demonstrate that the F-PA-SP copolymer has been successfully synthesized, and dynamic light scattering and transmission electron microscopy analyses indicate that the synthesized latex has presented a uniform particle size of approximately 200 nm. X-ray photoelectron spectroscopy, atomic force microscopy, and water contact angle (WCA) analyses were used to investigate the surface properties of the F-PA-SP coating and demonstrate that its hydrophobicity is enhanced by the addition of a fluorinated acrylic monomer. The photochromic properties of the coating were investigated by UV/vis spectroscopy, and the results reveal that the F-PA-SP coating possesses better photoresponsiveness, fatigue resistance, and photoreversibility under UV/vis irradiation than the coating prepared using fluorinated polyacrylate/SP blended latex. Moreover, the WCA of the F-PA-SP coating subjected to UV/vis irradiation shows minimal changes and retains its excellent hydrophobicity. Finally, the F-PA-SP latex was applied to cellulosic paper, and the resulting photochromic paper exhibits outstanding reversible color changes and hydrophobicity.

9.
Am J Physiol Cell Physiol ; 313(6): C612-C620, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29021196

RESUMO

(Pro)renin receptor (PRR), a component of the renin-angiotensin system, has emerged as a new regulator of collecting duct function. The present study was designed to investigate the role of PRR in high salt-induced apoptosis in cultured mouse inner medullary collecting duct cells, mIMCD-K2 cells. Exposure to high NaCl at 550 mosM/kgH2O increased PRR protein abundance, as did exposure to mannitol, sodium gluconate, or choline chloride. This was accompanied by upregulation of the abundance of phosphorylated NF-κB p65 protein. NF-κB inhibition with QNZ, caffeic acid phenethyl ester, or small interfering RNA (siRNA)-mediated silencing of NF-κB p65 attenuated high-NaCl-induced PRR upregulation. Exposure to high salt for 24 h induced apoptosis, as assessed by immunoblotting and immunocytochemistry analysis of cleaved caspase-3 and flow cytometry analysis of the number of apoptotic cells. High-NaCl-induced apoptosis was attenuated by a PRR decoy inhibitor, PRO20, or siRNA-mediated silencing of NF-κB p65. These results show that induction of PRR expression by exposure to high NaCl occurs through activation of NF-κB, thus contributing to cell apoptosis.


Assuntos
Apoptose/fisiologia , Túbulos Renais Coletores/metabolismo , NF-kappa B/metabolismo , Receptores de Superfície Celular/biossíntese , Cloreto de Sódio/toxicidade , Regulação para Cima/fisiologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Medula Renal/efeitos dos fármacos , Medula Renal/metabolismo , Túbulos Renais Coletores/efeitos dos fármacos , Camundongos , NF-kappa B/antagonistas & inibidores , RNA Interferente Pequeno/farmacologia , Regulação para Cima/efeitos dos fármacos , Receptor de Pró-Renina
10.
J Am Soc Nephrol ; 27(10): 3022-3034, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27000064

RESUMO

Within the kidney, the (pro)renin receptor (PRR) is predominantly expressed in the collecting duct (CD), particularly in intercalated cells, and it is regulated by the PGE2 receptor EP4 Notably, EP4 also controls urinary concentration through regulation of aquaporin 2 (AQP2). Here, we tested the hypothesis that sequential activation of EP4 and PRR determines AQP2 expression in the CD, thus mediating the antidiuretic action of vasopressin (AVP). Water deprivation (WD) elevated renal PRR expression and urinary soluble PRR excretion in rats. Intrarenal infusion of a PRR decoy peptide, PRO20, or an EP4 antagonist partially prevented the decrease in urine volume and the increase in urine osmolality and AQP2 expression induced by 48-hour WD. In primary cultures of rat inner medullary CD cells, AQP2 expression induced by AVP treatment for 24 hours depended on sequential activation of the EP4 receptor and PRR. Additionally, mice lacking PRR in the CD exhibited increased urine volume and decreased urine osmolality under basal conditions and impaired urine concentrating capability accompanied by severe volume loss and a dangerous level of plasma hyperosmolality after WD. Together, these results suggest a previously undescribed linear AVP/PGE2/EP4/PRR pathway in the CD for regulation of AQP2 expression and urine concentrating capability.


Assuntos
Diurese/fisiologia , Receptores de Superfície Celular/fisiologia , Receptores de Prostaglandina E Subtipo EP4/fisiologia , Vasopressinas/fisiologia , Animais , Túbulos Renais Coletores , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley , Receptor de Pró-Renina
11.
Research (Wash D C) ; 7: 0317, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38357698

RESUMO

Silica glass, known for its brittleness, weight, and non-biodegradable nature, faces challenges in finding suitable alternatives. Transparent wood, made by infusing polymers into wood, shows promise but is hindered by limited availability of wood in China and fire risks associated with its use. This study explores the potential of utilizing bamboo, which has a shorter growth cycle, as a valuable resource for developing flame-retardant, smoke-suppressing, and superhydrophobic transparent bamboo. A 3-layered flame-retardant barrier, composed of a top silane layer, an intermediate layer of SiO2 formed through hydrolysis-condensation of Na2SiO3 on the surface, and an inner layer of Na2SiO3, has been confirmed to be effective in reducing heat release, slowing flame spread, and inhibiting the release of combustible volatiles, toxic smoke, and CO. Compared to natural bamboo and other congeneric transparent products, the transparent bamboo displays remarkable superiority, with the majority of parameters being notably lower by an entire order of magnitude. It achieves a long ignition time of 116 s, low total heat release (0.7 MJ/m2), low total smoke production (0.063 m2), and low peak CO concentration (0.008 kg/kg). Moreover, when used as a substrate for perovskite solar cells, the transparent bamboo displays the potential to act as a light management layer, leading to a marked efficiency enhancement of 15.29%. The excellent features of transparent bamboo make it an enticing choice for future advancements in flame-retardant glasses and optical devices.

12.
Br J Pharmacol ; 181(5): 640-658, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37702564

RESUMO

BACKGROUND AND PURPOSE: Atherosclerosis induced by cyclosporine A (CsA), an inhibitor of the calcineurin/nuclear factor of activated T cells (NFAT) pathway, is a major concern after organ transplantation. However, the atherosclerotic mechanisms of CsA remain obscure. We previously demonstrated that calcineurin/NFAT signalling inhibition contributes to atherogenesis via suppressing microRNA-204 (miR-204) transcription. We therefore hypothesised that miR-204 is involved in the development of CsA-induced atherosclerosis. EXPERIMENTAL APPROACH: ApoE-/- mice with macrophage-miR-204 overexpression were generated to determine the effects of miR-204 on CsA-induced atherosclerosis. Luciferase reporter assays and chromatin immunoprecipitation sequencing were performed to explore the targets mediating miR-204 effects. KEY RESULTS: CsA alone did not significantly affect atherosclerotic lesions or serum lipid levels. However, it exacerbated high-fat diet-induced atherosclerosis and hyperlipidemia in C57BL/6J and ApoE-/- mice, respectively. miR-204 levels decreased in circulating monocytes and plaque lesions during CsA-induced atherosclerosis. The upregulation of miR-204 in macrophages inhibited CsA-induced atherosclerotic plaque formation but did not affect serum lipid levels. miR-204 limited the CsA-induced foam cell formation by reducing the expression of the scavenger receptors SR-BII and CD36. SR-BII was post-transcriptionally regulated by mature miR-204-5p via 3'-UTR targeting. Additionally, nuclear-localised miR-204-3p prevented the CsA-induced binding of Ago2 to the CD36 promoter, suppressing CD36 transcription. SR-BII or CD36 expression restoration dampened the beneficial effects of miR-204 on CsA-induced atherosclerosis. CONCLUSION AND IMPLICATIONS: Macrophage miR-204 ameliorates CsA-induced atherosclerosis, suggesting that miR-204 may be a potential target for the prevention and treatment of CsA-related atherosclerotic side effects.


Assuntos
Aterosclerose , MicroRNAs , Placa Aterosclerótica , Animais , Camundongos , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Aterosclerose/induzido quimicamente , Aterosclerose/genética , Calcineurina/metabolismo , Antígenos CD36/metabolismo , Ciclosporina/efeitos adversos , Ciclosporina/metabolismo , Lipídeos , Macrófagos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Placa Aterosclerótica/induzido quimicamente , Placa Aterosclerótica/metabolismo
13.
Org Lett ; 25(11): 1974-1977, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36920185

RESUMO

An efficient rhodium-catalyzed dearomative rearrangement of 2-oxypyridines with quinone diazides has been developed for the direct synthesis of N-arylated pyridones, in which a novel 1,6-O-to-O rather than 1,4-O-to-C acyl rearrangement has been achieved under mild reaction conditions.

14.
iScience ; 26(2): 105964, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36818307

RESUMO

Traditional electrode materials still face vital challenges of few active sites, low porosity, complex synthesis process, and low specific capacitance. Herein, N-doped and 3D hierarchical porous graphene nanofoam (N-GNF) is created on carbon fibers (CFs) by employing a facile, fast, and environmentally friendly strategy of N2 plasma activation. After an appropriated N2 plasma activation, the graphene nanosheets (GNSs) synthesized by Ar/CH4 plasma deposition transform into N-GNF successfully. N doping donates rich active sites and increases the hydrophilia, while hierarchical nanoarchitecture exposes an enlarged effective contact area at the interface between electrode and electrolyte and affords sufficient space for accommodating more electrolytes. The as-assembled flexible N-GNF@CFs//Zn NSs@CFs Zn ion capacitor delivered a high energy density of 105.2 Wh kg-1 at 378.6 W kg-1 and initial capacity retention of 87.9% at the current of 2 A g-1 after a long cycle of 10,000.

15.
Sci Total Environ ; 882: 163593, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37087015

RESUMO

Parabens, as the synthetic preservatives, have caused universal environmental contamination and human exposure. Whether parabens could disturb neuroendocrine system was still ambiguous. In this study, the effects of four commonly-used parabens, i.e. methyl paraben (MeP), ethyl paraben (EtP), propyl paraben (PrP) and butyl paraben (BuP), were tested on the neuroendocrine system of zebrafish larvae by investigating the swimming behavior, the related hormones and biomarkers in the hypothalamic-pituitary-interrenal (HPI) axis. The results showed that all test chemicals significantly reduced the swimming distance and mean velocity of zebrafish larvae. The adrenocorticotropic hormone (ACTH) levels in zebrafish larvae were significantly increased, while the cortisol levels were obviously decreased by paraben exposure. The transcriptional analysis showed that the expressions of the target genes including gr, mr and crhr2 in the HPI axis were mostly down-regulated. The exploration of the initial molecular event showed that parabens could bind with the glucocorticoid receptor (GR) and trigger its transactivation, according to MDA-kb2 luciferase assay and molecular docking analysis. The interaction of parabens with the GR included the hydrogen bond and hydrophobic interaction. The findings herein revealed the potential deleterious effects of parabens on the neuroendocrine system of zebrafish larvae, thus accumulating the in vivo toxicological data on this kind of food preservatives.


Assuntos
Poluentes Ambientais , Parabenos , Humanos , Animais , Parabenos/análise , Peixe-Zebra/metabolismo , Poluentes Ambientais/análise , Simulação de Acoplamento Molecular , Exposição Ambiental/análise , Sistemas Neurossecretores
16.
Org Lett ; 24(8): 1637-1641, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35191701

RESUMO

An enantioselective cyclopropanation reaction of N-substituted 2-pyridones with diazo compounds has been realized by using a chiral rhodium complex as the catalyst, and the corresponding chiral cyclopropanes could be formed in good yields with high enantioselectivities. Moreover, using acceptor-acceptor dimethyl 2-diazomalonate as the carbene precursor, a novel 1,4-rearrangement of a Boc group from N to C has also been discovered under rhodium catalysis.

17.
Front Physiol ; 13: 784521, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35222071

RESUMO

Phosphate (Pi) is one of the basic necessities required for sustenance of life and its metabolism largely relies on excretory function of the kidney, a process chiefly under the endocrine control of bone-derived fibroblast growth factor 23 (FGF23). However, knowledge gap exists in understanding the regulatory loop responsible for eliciting phophaturic response to Pi treatment. Here, we reported a novel role of (pro)renin receptor (PRR) in mediating phosphaturic response to Pi treatment via upregulation of FGF23 production. Male Sprague-Dawley rats were pretreated for 5 days via osmotic pump-driven infusion of a PRR antagonist PRO20 or vehicle, and then treated with high Pi (HP) solution as drinking fluid for the last 24 h. PRO20 reduced HP-induced Pi excretion by 42%, accompanied by blunted upregulation of circulating FGF23 and parathyroid hormone (PTH) and downregulation of renal Na/Pi-IIa expression. In cultured osteoblast cells, exposure to HP induced a 1.56-fold increase in FGF23 expression, which was blunted by PRO20 or siRNA against PRR. Together, these results suggest that activation of PRR promotes phosphaturic response through stimulation of FGF23 production and subsequent downregulation of renal Na/Pi-IIa expression.

18.
Eco Environ Health ; 1(3): 198-199, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38075600

RESUMO

[This corrects the article DOI: 10.1016/j.eehl.2022.04.003.].

19.
Eco Environ Health ; 1(1): 31-45, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38078200

RESUMO

The environmental and health impacts from the massive discharge of chemicals and subsequent pollution have been gaining increasing public concern. The unintended exposure to different pollutants, such as heavy metals, air pollutants and organic chemicals, may cause diverse deleterious effects on human bodies, resulting in the incidence and progression of different diseases. The article reviewed the outbreak of environmental pollution-related public health emergencies, the epidemiological evidence on certain pollution-correlated health effects, and the pathological studies on specific pollutant exposure. By recalling the notable historical life-threatening disasters incurred by local chemical pollution, the damning evidence was presented to criminate certain pollutants as the main culprit for the given health issues. The epidemiological data on the prevalence of some common diseases revealed a variety of environmental pollutants to blame, such as endocrine-disrupting chemicals (EDCs), fine particulate matters (PMs) and heavy metals. The retrospection of toxicological studies provided illustrative clues for evaluating ambient pollutant-induced health risks. Overall, environmental pollution, as the hidden culprit, should answer for the increasing public health burden, and more efforts are highly encouraged to strive to explore the cause-and-effect relationships through extensive epidemiological and pathological studies.

20.
Carbohydr Polym ; 296: 119905, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36088018

RESUMO

A nature-inspired strategy is developed to build dual-network hydrogels made up of rigid graphene oxide-functionalized nanocellulose (GO@NC) network and flexible poly[acrylamide-co-(acrylic acid)] (poly(AAm-co-AAc)) network. A pre-stretching method is used to form a muscle-shape anisotropic architecture. The penetration of poly(AAm-co-AAc) flexible network relieves the stiffness of NC network, thus improving the average elongation at break from 86.2 % to 748.0 %. Compared with the poly(AAm-co-AAc), the average rupture tensile strength rises remarkably by 228.6 %. The dual-crosslinked strategy endows the GO@NC-poly(AAm-co-AAc) hydrogels with a fast, stable and repeatable self-healing ability, which can achieve 85.0 % of healing efficiency after only 600 s of self-healing and maintain 76.2 % of initial strength after 10 cycles of breaking-self-healing. The superb self-healing ability is similar to the muscle function. For potential applications, the hydrogels can achieve real-time, stable, and long-term sensing as smart wearable strain sensors (high gauge factor: 5.13), and can effectively purify Sudan IV wastewater as green recyclable adsorbents.


Assuntos
Grafite , Hidrogéis , Acrilamidas , Poli A , Resistência à Tração
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