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1.
Int J Biol Macromol ; 274(Pt 1): 133246, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38908633

RESUMO

The mixed infection of duck hepatitis A virus 3 (DHAV-3) and novel duck reovirus (NDRV) has caused significant losses to the global duck farming industry. On-site point-of-care testing of viruses plays a crucial role in the early diagnosis, prevention, and disease control. Here, we proposed an RPA-CRISPR Cas12a/Cas13a one-pot strategy (DRCFS) for rapid and simultaneous detection of DHAV-3 and NDRV. This method integrated the reaction of RPA and CRISPR Cas12a/Cas13a in a single tube, eliminating the need to open the lid during the intermediate processes and thereby avoiding aerosol contamination. On this basis, we proposed a dual RPA-CRISPR strategy coupled with a lateral flow analysis platform (DRC-LFA). This circumvented the necessity for complex instruments, enabling direct visual interpretation of results, making the test more accessible and user-friendly. Our findings demonstrated that the DRCFS method could detect DHAV-3 and NDRV at concentrations as low as 100 copy/µL, while DRC-LFA achieved limit of 101 copies/µL within 35 min. Furthermore, when DRCFS, DRC-LFA, and qPCR were employed collectively for clinical samples analysis, all three methods yielded consistent results. The specificity, sensitivity, and user-friendly of these methods rendered them invaluable for on-site virus detection.

2.
Sci Bull (Beijing) ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38910107

RESUMO

Highly selective production of value-added multicarbon (C2+) products via electrochemical CO2 reduction reaction (eCO2RR) on polycrystalline copper (Cu) remains challenging. Herein, the facile surface modification using poly (α-ethyl cyanoacrylate) (PECA) is presented to greatly enhance the C2+ selectivity for eCO2RR over polycrystalline Cu, with Faradaic efficiency (FE) towards C2+ products increased from 30.1% for the Cu electrode to 72.6% for the obtained Cu-PECA electrode at -1.1 V vs. reversible hydrogen electrode (RHE). Given the well-determined FEs towards C2+ products, the partial current densities for C2+ production could be estimated to be -145.4 mA cm-2 for the Cu-PECA electrode at -0.9 V vs. RHE in a homemade flow cell. In-situ spectral characterizations and theoretical calculations reveal that PECA featured with electron-accepting -C≡N and -COOR groups decorated onto the Cu electrode could inhibit the adsorption of *H intermediates and stabilize the *CO intermediates, given the redistributed interfacial electron density and the raised energy level of d-band center (Ed) of Cu active sites, thus facilitating the C-C coupling and then the C2+ selective production. This study is believed to be guidable to the modification of electrocatalysts and electrodes with polymers to steer the surface adsorption behaviors of reaction intermediates to realize practical eCO2RR towards value-added C2+ products with high activity and selectivity.

3.
Cell Death Dis ; 15(5): 316, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710691

RESUMO

S100 calcium-binding protein 16 (S100A16) is implicated in both chronic kidney disease (CKD) and acute kidney injury (AKI). Previous research has shown that S100A16 contributes to AKI by facilitating the ubiquitylation and degradation of glycogen synthase kinase 3ß (GSK3ß) and casein kinase 1α (CK1α) through the activation of HMG-CoA reductase degradation protein 1 (HRD1). However, the mechanisms governing S100A16-induced HRD1 activation and the upregulation of S100A16 expression in renal injury are not fully understood. In this study, we observed elevated expression of Hypoxia-inducible Factor 1-alpha (HIF-1α) in the kidneys of mice subjected to ischemia-reperfusion injury (IRI). S100A16 deletion attenuated the increased HIF-1α expression induced by IRI. Using a S100A16 knockout rat renal tubular epithelial cell line (NRK-52E cells), we found that S100A16 knockout effectively mitigated apoptosis during hypoxic reoxygenation (H/R) and cell injury induced by TGF-ß1. Our results revealed that H/R injuries increased both protein and mRNA levels of HIF-1α and HRD1 in renal tubular cells. S100A16 knockout reversed the expressions of HIF-1α and HRD1 under H/R conditions. Conversely, S100A16 overexpression in NRK-52E cells elevated HIF-1α and HRD1 levels. HIF-1α overexpression increased HRD1 and ß-catenin while decreasing GSK-3ß. HIF-1α inhibition restored HRD1 and ß-catenin upregulation and GSK-3ß downregulation by cellular H/R injury. Notably, Chromatin immunoprecipitation (ChIP) and luciferase reporter assays demonstrated HIF-1α binding signals on the HRD1 promoter, and luciferase reporter gene assays confirmed HIF-1α's transcriptional regulation of HRD1. Additionally, we identified Transcription Factor AP-2 Beta (TFAP2B) as the upregulator of S100A16. ChIP and luciferase reporter assays confirmed TFAP2B as a transcription factor for S100A16. In summary, this study identifies TFAP2B as the transcription factor for S100A16 and demonstrates HIF-1α regulation of HRD1 transcription within the S100A16-HRD1-GSK3ß/CK1α pathway during renal hypoxia injury. These findings provide crucial insights into the molecular mechanisms of kidney injury, offering potential avenues for therapeutic intervention.


Assuntos
Glicogênio Sintase Quinase 3 beta , Subunidade alfa do Fator 1 Induzível por Hipóxia , Animais , Glicogênio Sintase Quinase 3 beta/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Camundongos , Ratos , Proteínas S100/metabolismo , Proteínas S100/genética , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Transdução de Sinais , Masculino , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Injúria Renal Aguda/genética , Camundongos Endogâmicos C57BL , Rim/metabolismo , Rim/patologia , Apoptose , Linhagem Celular , Hipóxia Celular , Camundongos Knockout
4.
Cancer Lett ; 590: 216868, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38593920

RESUMO

While previous studies have indicated the involvement of Isthmin 1 (ISM1), a secreted protein, in cancer development, the precise mechanisms have remained elusive. In this study, we unveiled that ISM1 is significantly overexpressed in both the blood and tissue samples of colorectal cancer (CRC) patients, correlating with their poor prognosis. Functional experiments demonstrated that enforced ISM1 expression significantly enhances CRC proliferation, migration, invasion and tumor growth. Notably, our investigation reveals an interaction of ISM1 with epidermal growth factor receptor (EGFR), a member of the receptor tyrosine kinase (RTK) family of CRC cells. The binding of ISM1 triggered EGFR activation and initiate downstream signaling pathways. Meanwhile, intracellular ISM1 interacted with Y-box binding protein 1 (YBX1), enhancing its transcriptional regulation on EGFR. Furthermore, our research uncovered the regulation of ISM1 expression by the hypoxia-inducible transcription factor HIF-1α in CRC cells. Mechanistically, we identified HIF-1α as a direct regulator of ISM1, binding to a hypoxia response element on its promoter. This novel mechanism illuminated potential therapeutic targets, offering insights into restraining HIF-1α/ISM1/EGFR-driven CRC progression and metastasis.


Assuntos
Proliferação de Células , Neoplasias Colorretais , Progressão da Doença , Receptores ErbB , Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia , Proteína 1 de Ligação a Y-Box , Humanos , Receptores ErbB/metabolismo , Receptores ErbB/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Proteína 1 de Ligação a Y-Box/metabolismo , Proteína 1 de Ligação a Y-Box/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Animais , Movimento Celular , Linhagem Celular Tumoral , Camundongos , Masculino , Transdução de Sinais , Feminino , Camundongos Nus , Células HCT116 , Prognóstico
5.
Chemistry ; 30(15): e202303895, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38198245

RESUMO

To promote interfacial charge transfer process and accelerate surface water oxidation reaction kinetics for photoelectrochemical (PEC) water splitting over n-type Silicon (n-Si) based photoanodes, herein, starting with surface stabilized n-Si/CoOx , a NiOx /NiFeOOH composite overlayer was coated by atomic layer deposition and spray coating to fabricate the multilayer structured n-Si/CoOx /NiOx /NiFeOOH photoanode. Encouragingly, the obtained n-Si/CoOx /NiOx /NiFeOOH photoanode exhibits much increased PEC activity for water splitting, with onset potential cathodically shifted to ~0.96 V vs. RHE and photocurrent density increased to 22.6 mA cm-2 at 1.23 V vs. RHE for OER, as compared to n-Si/CoOx , even significantly surpassing the counterpart n-Si/CoOx /NiOx /FeOOH and n-Si/CoOx /NiOx /NiOOH photoanodes. Photophysical and electrochemical characterizations evidence that the deposited CoOx /NiOx /NiFeOOH composite overlayer would create large band bending and strong built-in electric field at the introduced cascading interfaces, thereby producing a large photovoltage of 650 mV to efficiently accelerate charge transfer from the n-Si substrate to the electrolyte for water oxidation. Furthermore, the surface oxygen vacancy enriched NiFeOOH overlayer could effectively catalyze the water oxidation reaction by thermodynamically reducing the energy barrier of rate determining step for OER.

6.
Br J Pharmacol ; 181(11): 1596-1613, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38124222

RESUMO

BACKGROUND AND PURPOSE: Oat ß-glucan could ameliorate epidermal hyperplasia and accelerate epidermal barrier repair. Dectin-1 is one of the receptors of ß-glucan and many biological functions of ß-glucan are mediated by Dectin-1. Dectin-1 promotes wound healing through regulating the proliferation and migration of skin cells. Thus, this study aimed to investigate the role of oat ß-glucan and Dectin-1 in epidermal barrier repair. EXPERIMENTAL APPROACH: To investigate the role of Dectin-1 in the epidermal barrier, indicators associated with the recovery of a damaged epidermal barrier, including histopathological changes, keratinization, proliferation, apoptosis, differentiation, cell-cell junctions and lipid content were compared between WT and Dectin-1-/- mice. Further, the effect of oat ß-glucan on the disruption of the epidermal barrier was also compared between WT and Dectin-1-/- mice. KEY RESULTS: Dectin-1 deficiency resulted in delayed recovery and marked keratinization, as well as abnormal levels of keratinocyte differentiation, cell-cell junctions and lipid synthesis during the restoration of the epidermal barrier. Oat ß-glucan significantly reduces epidermal hyperplasia, promotes epidermal differentiation, increases cell-cell junction expression, promotes lipid synthesis and ultimately accelerates the recovery of damaged epidermal barriers via Dectin-1. Oat ß-glucan could promote CaS receptor expression and activate the PPAR-γ signalling pathway via Dectin-1. CONCLUSION AND IMPLICATIONS: Oat ß-glucan promote the recovery of damaged epidermal barriers through promoting epidermal differentiation, increasing the expression of cell-cell junctions and lipid synthesis through Dectin-1. Dectin-1 deficiency delay the recovery of epidermal barriers, which indicated that Dectin-1 may be a potential target in epidermal barrier repair.


Assuntos
Diferenciação Celular , Epiderme , Lectinas Tipo C , Regulação para Cima , beta-Glucanas , Animais , Lectinas Tipo C/metabolismo , beta-Glucanas/farmacologia , Epiderme/metabolismo , Epiderme/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Camundongos , Regulação para Cima/efeitos dos fármacos , Camundongos Knockout , Camundongos Endogâmicos C57BL , Junções Intercelulares/efeitos dos fármacos , Junções Intercelulares/metabolismo , Masculino , Cicatrização/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos
7.
Cell Mol Life Sci ; 80(6): 168, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37249651

RESUMO

Hepatic glucose and lipid metabolism disorders promote the development and progression of type 2 diabetes mellitus (T2DM), yet the underlying mechanisms are not fully understood. Here, we identify tripartite motif-containing protein 21 (TRIM21), a class IV TRIM family member, as a pivotal regulator of hepatic metabolism in T2DM for the first time. Bioinformatic analysis suggests that TRIM21 expression is significantly reduced in T2DM patients. Intriguingly, in a mouse model of obese diabetes, TRIM21 expression is predominantly reduced in the liver rather than in other metabolic organs. It is further demonstrated that hepatic overexpression of TRIM21 significantly ameliorates glucose intolerance, insulin resistance, hepatic steatosis, and dyslipidemia in obese diabetic mice. In contrast, the knockdown of TRIM21 promotes glucose intolerance, insulin resistance, and triglyceride accumulation. Mechanistically, both phosphoenolpyruvate carboxykinase 1 (PEPCK1) and fatty acid synthase (FASN) are the hepatic targets of TRIM21. We revealed that TRIM21 promotes the degradation of PEPCK1 and FASN through a direct protein-protein interaction mediated K48-linked ubiquitination. Notably, overexpression of PEPCK1 and FASN essentially abolished the beneficial effects achieved by TRIM21 overexpression in obese diabetic mice. Overall, our data demonstrate that TRIM21 is a novel regulator of hepatic metabolic disorder, and suggest TRIM21 as a promising therapeutic target for T2DM.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Intolerância à Glucose , Resistência à Insulina , Transtornos do Metabolismo dos Lipídeos , Animais , Camundongos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Ácido Graxo Sintases/metabolismo , Ácido Graxo Sintases/uso terapêutico , Glucose/metabolismo , Intolerância à Glucose/metabolismo , Transtornos do Metabolismo dos Lipídeos/metabolismo , Lipídeos , Fígado/metabolismo , Obesidade/metabolismo , Ubiquitinação , Humanos
8.
Front Pharmacol ; 13: 1036013, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386220

RESUMO

The integrity of skin tissue structure and function plays an important role in maintaining skin rejuvenation. Ultraviolet (UV) radiation is the main environmental factor that causes skin aging through photodamage of the skin tissue. Cryptotanshinone (CTS), an active ingredient mianly derived from the Salvia plants of Lamiaceae, has many pharmacological effects, such as anti-inflammatory, antioxidant, and anti-tumor effects. In this study, we showed that CTS could ameliorate the photodamage induced by UV radiation in epidermal keratinocytes (HaCaT) and dermal fibroblasts (HFF-1) when applied to the cells before exposure to the radiation, effectively delaying the aging of the cells. CTS exerted its antiaging effect by reducing the level of reactive oxygen species (ROS) in the cells, attenuating DNA damage, activating the nuclear factor E2-related factor 2 (Nrf2) signaling pathway, and reduced mitochondrial dysfunction as well as inhibiting apoptosis. Further, CTS could promote mitochondrial biosynthesis in skin cells by activating the AMP-activated protein kinase (AMPK)/sirtuin-1 (SIRT1)/peroxisome proliferator-activated receptor-γ co-activator-1α (PGC-1α) signaling pathway. These findings demonstrated the protective effects of CTS against UV radiation-induced skin photoaging and provided a theoretical and experimental basis for the application of CTS as an anti-photodamage and anti-aging agent for the skin.

9.
Ann Transl Med ; 10(20): 1104, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36388783

RESUMO

Background: The inhibition of fibroblast growth factor 18 (FGF18) promotes the transition of hair follicles (HFs) from the telogen phase to the anagen phase. Cucurbitacin has been shown to have a good effect in promoting hair cell growth. This study explored the potential effect of cucurbitacin on hair growth and its effect on FGF18 expression in mice. Methods: Male C57BL/6J mice were randomly divided into the following two groups: (I) the vehicle group; and (II) the cucurbitacin group. Matrix cream and cucurbitacin cream were applied to the depilated skin on the back of the vehicle group mice and the cucurbitacin group mice, respectively. On days 3, 6, 9, 12, 15, and 18, the hair growth in the depilated dorsal skin of the mice was recorded with a digital camera and a HF detector, and the HF cycle status of the mice was observed by hematoxylin and eosin (H&E) staining. In addition, the level of FGF18 messenger ribonucleic acid (mRNA) in the dorsal skin was measured on days 15 and 18 by quantitative real-time polymerase chain reaction (qRT-PCR), while the level of FGF18 protein was measured by western blot and immunofluorescence staining. Results: The dorsal skin to which the cucurbitacin cream was applied began to darken on day 6 and grew hairs on day 9, which was 3 days earlier than the dorsal skin to which the matrix cream was applied. The H&E staining revealed a transition from the telogen phase to the anagen phase 3 days earlier for the cucurbitacin cream-treated skin than the matrix cream-treated skin. In addition, the skin treated with cucurbitacin cream also showed a significant decrease in FGF18 mRNA as seen by qRT-PCR, and reduced FGF18 protein levels as detected by western blot and immunofluorescence staining compared to the skin treated with matrix cream only. Conclusions: Cucurbitacin significantly reduced the levels of FGF18 mRNA and protein in the dorsal skin of mice to accelerate the HFs to enter the anagen phase earlier, thereby promoting the regeneration of hair. Thus, cucurbitacin can be considered a new and valuable agent for the development of anti-hair loss products.

10.
J Org Chem ; 87(7): 4702-4711, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35316058

RESUMO

Recently, a novel [2+2] cycloaddition between the classical Ih-C60 and a fluorenylideneallene complex has been achieved experimentally. In the fullerene-fluorene dyad product, stereo- and regio-selectivities were found in the experiment, but the reasons are still unknown. Our theoretical studies suggest that, based on a diradical pathway, the structural selectivity of the product strongly depends on the structural/electronic features of the fluorenylideneallene and C60 complexes. When the R1 group in fluorenylideneallene denotes the H atom, the E-type product is more stable than the Z-type one, whereas other bulkier R1 groups lead to the reverse due to their steric hindrance. The π orbital conjugation between the fluorenyl group and the Cß═Cγ bond in fluorenylideneallene is the main reason for the high selectivity of ß,γ-cycloaddition. Analyses of both frontier orbitals and spin density for the intermediate structure suggest a diradical pathway of the reaction between fluorenylideneallene and C60 and uncover a decisive role of the LUMO of C60 toward regio-selectivity, which conduces to a high selectivity of the (6,6)-addition product.

11.
Inorg Chem ; 60(15): 11287-11296, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34286976

RESUMO

Recently, one η1-coordinated complex of endohedral metallofullerene (EMF) Y@C2v(9)-C82[Re(CO)5] has been synthesized and characterized with a highly efficient radical-coupling methodology by performing a photochemical reaction between Y@C2v(9)-C82 and [Re(CO)5]2 complexes. Theoretical investigations with the density functional theory reveal that this complex is stabilized by an ionic C-Re bond. The reactions of M@C2v(9)-C82 (M = Sc, Y, La) with [Re(CO)5]2 suggest that the reaction energies differ little because of similar single occupied molecular orbitals (SOMOs) of M@C2v(9)-C82. In the reactions of Y@C2v(9)-C82 with various transition-metal complexes [M'Ln]2 (M' = Mn, Tc, Re, Fe, Ru, Os, Co, Rh, Ir), the C-M' bonds with Mn, Tc, Re, Fe, Ru, and Os can stably exist, whereas those with Co, Rh, and Ir are unstable. Further analyses disclose that, in each element group, the stability of the C-M' bond is mainly determined by the bond energy of the M'-M' bond, which is related to the dσ orbital of the M'Ln species. Moreover, the very-low-energy dσ orbitals and large geometrical distortions of M'(CO)4 (M' = Co, Rh, Ir) lead to poor stabilities of the C-M' (M' = Co, Rh, Ir) bonds. As comparison, the reactions of Y@Cs(6)-C82 and La@C72 have been investigated. The Y@Cs(6)-C82 structure is more reactive toward the [M'Ln]2 complexes than Y@C2v(9)-C82 thanks to a lower SOMO of Y@Cs(6)-C82 than that of Y@C2v(9)-C82, which derives from position change of the Y atom in Cs(6)-C82 during the reactions. However, the formation of [Y@Cs(6)-C82]2 suppresses the formation of several C-M' bonds. The reactivity of La@C72 is weak due to a high LUMO+1 of C72, which leads to a high SOMO of La@C72. We believe that this theoretical study provides primary principles of radical-coupling reactions of EMFs and will be valuable for future research of organometallic complexes of fullerene.

12.
Inorg Chem ; 60(4): 2425-2436, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33497217

RESUMO

There is still dispute over the stability of endohedral metallofullerenes (EMFs) M2C2n, and recently, multiform lutetium-based dimetallofullerenes have been dropped in experiments. The thermodynamic stabilities of Lu2C86 EMFs are revealed by density functional theory (DFT) in conjunction with statistical thermodynamic analyses. Inevitably, besides the experimentally reported Lu2@C2v(63751)-C86, Lu2@Cs(63750)-C86, and Lu2@Cs(63757)-C86, other three metal carbide clusterfullerenes, Lu2C2@D2d(51591)-C84, Lu2C2@C1(51383)-C84, and Lu2C2@Cs(id207430)-C84, rather than Lu2@C86 are first characterized as thermodynamically stable isomers of Lu2C86. Specially, the Cs(id207430)-C84 is a newly non-classical fullerene containing one heptagon, which is stabilized via encaging Lu2C2. Another interesting phenomenon is that the outer fullerene cages of thermodynamically stable Lu2C82-88 molecules are geometrically connected through C2 addition/loss and Stone-Wales (SW) transformation, suggesting a special relationship between thermodynamic stabilities and geometries of Lu2C82-88 EMFs. Furthermore, the electronic configurations of (Lu2)4+@C864- and (Lu2C2)4+@C844- were confirmed. A significantly stable two-center two-electron (2c-2e) Lu-Lu σ single bond is formed in Lu2@C86. By comparing M-M bonds in M2@C2v(63751)-C86 (M = Sc, Y, La, and Lu), two significant factors, the valence atomic orbital (ns) of metal atoms and radius of M2+, are found to determine the stability of the M-M bond in the C2v(63751)-C86. Additionally, the simulated UV-vis-NIR spectra of thermodynamically stable Lu2C86 isomers were simulated, which further disclose their electronic features.

13.
Metabolism ; 114: 154349, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32888949

RESUMO

BACKGROUND: The functions of Acly in regulating nonalcoholic fatty liver disease (NAFLD) have been identified; however, the dynamic control of Acly expression under the pathological state of metabolic disorders has not been fully elucidated. Previous studies reported an ubiquitin-proteasome-mediated degradation of Acly, but the mechanism is still largely unknown. METHODS: Co-IP-based mass spectrum (MS/MS) assays were performed in HepG2 and Hepa1-6 hepatocytes and mouse liver tissue. The protein-protein interaction and ubiquitin modification of Hrd1 on Acly were confirmed by co-IP based immuno-blotting. Acetyl-CoA levels and lipogenesis rates were determined. The roles of Hrd1 on NAFLD and insulin resistance were tested by adenovirus-mediated overexpression in db/db mice or in separated primary hepatocytes. RESULTS: Hrd1, a subunit of the endoplasmic reticulum-associated degradation (ERAD) complex, interacted with and ubiquitinated Acly, thereby reducing its protein level. Hrd1 suppressed the acetyl-CoA level and inhibited lipogenesis through an Acly-dependent pathway. The expression of hepatic Hrd1 was negatively associated with NAFLD, whereas overexpression of Hrd1 ameliorated hepatic steatosis and enhanced insulin sensitivity, both in db/db mice and in separated mouse primary hepatocytes. CONCLUSIONS: Our results suggest that Acly, a master enzyme that regulates lipogenesis, is degraded by Hrd1 through ubiquitin modification. The activation of Hrd1 in hepatocytes might therefore represent a strategic approach for NAFLD therapy.


Assuntos
ATP Citrato (pro-S)-Liase/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/fisiologia , Animais , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Resistência à Insulina/fisiologia , Lipogênese/fisiologia , Camundongos , Espectrometria de Massas em Tandem
14.
Biochem Biophys Res Commun ; 529(2): 277-282, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32703423

RESUMO

BACKGROUND: Tangeretin, a flavonoid derived from citrus peel, showed anti-diabetic effects. However, the role of tangeretin on liver, the organ that act as target of insulin and play the central role in maintaining the blood glucose level control, is still largely unknown. The current study was designed to assess the effect of tangeretin on liver insulin sensitivity in vitro and in vivo. METHODS: Primary hepatocytes and mice were treated with different dose of tangeretin, parameters of insulin sensitivity, such as blood glucose levels, serum insulin levels, glucose tolerate test (GTT), insulin tolerate test (ITT), insulin stimulated IR-AKT pathway were analyzed. RESULTS: Primary hepatocytes treated with 10/20 µM tangeretin showed up-regulated insulin signaling pathway as well as the glycogen content, while the glucose output were reduced. Intragastric administration of tangeretin (25/50 mg/kg) also ameliorated the liver insulin sensitivity and improved the glucose homeostasis, both in wild type C57 mice and in db/db mice, a diabetic model. Tangeretin treatment dose-dependently suppressed the MEK-ERK1/2 pathway, while forced activation of p-ERK1/2 reversed the insulin sensitized effect of tangeretin. CONCLUSION: These results indicated that tangeretin enhanced the liver insulin sensitivity in vitro and in vivo, through suppressing the MEK-ERK1/2 pathway.


Assuntos
Flavonas/farmacologia , Hepatócitos/efeitos dos fármacos , Resistência à Insulina , Insulina/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Animais , Células Cultivadas , Citrus/química , Flavonas/química , Hepatócitos/metabolismo , Masculino , Camundongos Endogâmicos C57BL
15.
Bioengineered ; 11(1): 375-385, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32175802

RESUMO

Rhizomucor miehei lipase (RML) is a biocatalyst that widely used in laboratory and industrial. Previously, RML with a 70-amino acid propeptide (pRML) was cloned and expressed in P. pastoris. Recombinant strains with (strain containing 4-copy prml) and without ER stress (strain containing 2-copy prml) were obtained. However, the effective expression of pRML in P. pastoris by coexpressing ER-related elements in pRML-produced strain with or without ER stress has not been reported to date. In this study, an efficient way to produce functional pRML was explored in P. pastoris. The coexpression of protein folding chaperones, including PDI and ERO1, in different strains with or without ER stress, was investigated. PDI overexpression only increased pRML production in 4-copy strain from 705 U/mL to 1430 U/mL because it alleviated the protein folded stress, increased the protein concentration from 0.56  mg/mL to 0.65 mg/mL, and improved enzyme-specific activity from 1238 U/mg to 2186 U/mg. However, PDI coexpression could not improve pRML production in the 2-copy strain because it increased protein folded stress, while ERO1 coexpression in the two strains all had a negative effect on pRML expression. We also investigated the effect of the propeptide on the substrate specificity and the condition for pRML enzyme powder preparation. Results showed that the relative activity exceeded 80% when the substrates C8-C10 were detected at 35°C and pH 6, and C8-C12 at 45°C and pH 8. The optimal enzyme powder preparation pH was 7, and the maximum recovery rate for pRML was 73.19%.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Lipase/metabolismo , Pichia/enzimologia , Rhizomucor/enzimologia , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/genética , Regulação Fúngica da Expressão Gênica/genética , Regulação Fúngica da Expressão Gênica/fisiologia , Dobramento de Proteína
16.
Bioengineered ; 11(1): 241-250, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32091302

RESUMO

Lard is a by-product of animal processing. It is inexpensive compared with vegetable oils; however, its use is limited due to the high calorific value and high-saturated fatty acid content. While using lard as the source of free fatty acids (FFA) can significantly increase its utilization value. This study aimed to research the method on efficient hydrolysis of lard catalyzed by combi-lipases and assisted with ultrasound pretreatment. A 1,3-specific lipase from Rhizomucor miehei (termed pRML, 1540 U/mL) and a nonspecific mono- and diacylglycerol lipase from Penicillium cyclopium (termed MDL, 2000 U/mL) were used as biocatalysts. Results showed that the maximum hydrolysis rate of lard after 6 h at 45°C by using pRML and MDL alone was, respectively, 39.9% and 8.5%. When pRML combined with MDL (combi-lipases), hydrolysis rate can reach to 78.1%. While combi-lipases were assisted with 5 min ultrasound pretreatment before the reaction, the hydrolysis rate can further increase to 97%. The combi-lipases with different specificity and assisted with ultrasound pretreatment may be a useful technology for the enzyme production of FFA from complex lipid substrates, such as lard.


Assuntos
Gorduras na Dieta/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Lipase/metabolismo , Catálise , Hidrólise , Especificidade por Substrato
17.
New Phytol ; 222(3): 1507-1522, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30632163

RESUMO

miRNAs contribute to plant resistance against pathogens. Previously, we found that the function of miR398b in immunity in rice differs from that in Arabidopsis. However, the underlying mechanisms are unclear. In this study, we characterized the mutants of miR398b target genes and demonstrated that multiple superoxide dismutase genes contribute to miR398b-regulated rice immunity against the blast fungus Magnaporthe oryzae. Out of the four target genes of miR398b, mutations in Cu/Zn-Superoxidase Dismutase1 (CSD1), CSD2 and Os11g09780 (Superoxide DismutaseX, SODX) led to enhanced resistance to M. oryzae and increased hydrogen peroxide (H2 O2 ) accumulation. By contrast, mutations in Copper Chaperone for Superoxide Dismutase (CCSD) resulted in enhanced susceptibility. Biochemical studies revealed that csd1, csd2 and sodx displayed altered expression of CSDs and other superoxide dismutase (SOD) family members, leading to increased total SOD enzyme activity that positively contributed to higher H2 O2 production. By contrast, the ccsd mutant showed CSD protein deletion, resulting in decreased CSD and total SOD enzyme activity. Our results demonstrate the roles of different SODs in miR398b-regulated resistance to rice blast disease, and uncover an integrative regulatory network in which miR398b boosts total SOD activity to upregulate H2 O2 concentration and thereby improve disease resistance.


Assuntos
Resistência à Doença , Peróxido de Hidrogênio/metabolismo , MicroRNAs/metabolismo , Oryza/metabolismo , Doenças das Plantas/microbiologia , Superóxido Dismutase/metabolismo , Regulação para Baixo , Regulação da Expressão Gênica de Plantas , Magnaporthe , MicroRNAs/genética , Modelos Biológicos , Mutação/genética , Oryza/genética , Oryza/microbiologia , Espécies Reativas de Oxigênio/metabolismo
18.
ACS Appl Mater Interfaces ; 8(49): 33874-33887, 2016 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-27960415

RESUMO

Containing two nitrogen atoms, the electron-deficient pyrimidine ring has excellent coordinating capability with transition metal ions. However, compared with the widely used pyridine ring, applications of the pyrimidine ring in phosphorescent Ir(III) complexes are rare. In this research, two highly emissive pyrimidine-based mononuclear Ir(III) complexes and their corresponding dinuclear Ir(III) complexes were prepared with a simple one-pot reaction. The incorporation of the second Ir(III) center can lead to dramatic differences of both photophysical and electrochemical properties between the mono- and dinuclear complexes. Besides, these properties can also be fine-tuned with different substituents. Theoretical calculations have also been performed to understand their photophysical behaviors. The electroluminescent investigations demonstrate that the pyrimidine-based mono- and dinuclear Ir(III) complexes could show impressive device performance. The vacuum-deposited organic light-emitting diode (OLED) based on the mononuclear Ir(III) complex exhibited an external quantum efficiency (EQE) of 16.1% with almost no efficiency roll-off even at 10 000 cd m-2. More encouragingly, the solution-processed OLED based on the dinuclear Ir(III) complex achieved the outstanding EQE, current efficiency (CE), and power efficiency (PE) of 17.9%, 52.5 cd A-1, and 51.2 lm W-1, respectively, representing the highest efficiencies ever achieved by OLEDs based on dinuclear Ir(III) complexes.

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