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1.
Enzyme Microb Technol ; 132: 109409, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31731962

RESUMO

Zygosaccharomyces rouxii is a well-known salt-tolerant yeast. In our previous study, it was interesting that Z. rouxii could produce higher levels of 4-hydroxy-2, 5-dimethyl-3(2 H)-furanone in 120 g/L D-fructose and 180 g/L NaCl involved YPD medium at 5 d. In order to explore the resistance and furanone production mechanisms of Z. rouxii under D-fructose regulation, a comparative transcriptomics method in Z. rouxii was to set to find differentially expressed genes, the physiological and biochemical indexes (growth and cell morphology, lipid peroxidation and relative electrical conductivity, the antioxidant enzymes activity), and the expression of oxidoreductase activity genes. The results indicated that a larger number of different expressed genes at transcriptome analysis, such as the series antioxidant enzymes were related to the resistance characteristics. Research had confirmed that the living cell numbers and cell areas of D-fructose regulation group were significantly lower than the controls at the initial stage, while those higher than of the controls at the late stage. During the fermentation period, the lipid peroxidation and the relative electrical conductivity of the yeast cell membrane were increased. And also the D-fructose regulation group present lower inhibition superoxide anion ability. The activity of CAT in the D-fructose regulation group was always higher than that of the control group. Only the activity of GSH-Px was found to be significantly increased at 1 d except for other enzymes activities. Most of the oxidoreductase activity genes, such as especially the GSH-Px gene under D-fructose regulation conditions were expressed at higher levels than those of control groups. Combining the levels of transcription and enzymes activity data, those could understand that exogenous D-fructose had a stress effect on Z. rouxii at the early stage of culture. With the fermentation time progress, it was no longer a stressor substance for the Z. rouxii, and changed the nutrient to promote growth of Z. rouxii in the later stages. During the whole process, GSH-Px was the main defense enzyme and CAT was the sustained defense enzyme. Therefore, the experimental results might provide effective mechanisms in Z. rouxii for practical application of furanone production in the industry under exogenous D-fructose regulation.

2.
J Hazard Mater ; 382: 121007, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31445414

RESUMO

Fenton-like degradations of dimethyl phthalate (DMP) and phenolic compounds (phenol, catechol, resorcinol, and hydroquinone) in single and binary systems were investigated by focusing on the Fe(III)/Fe(II) redox cycle during the reaction processes. Quinone-like substances were generated and found to be responsible for the autocatalytic transformation of Fe(III) to Fe(II) in the Fenton-like process with DMP or phenolics. Moreover, phenolic compounds could accelerate the Fenton-like degradation of DMP, with an increased efficiency of H2O2 utilization. The effect of phenolic compounds on the degradation of DMP followed the order: catechol ≈ hydroquinone > resorcinol > phenol, which could be attributed to the interaction between quinone-like substances and iron ions. Hydroquinone-like substances accelerated the Fe(III)/(II) redox cycle. The formation of iron complexes between catechol-like substances and iron ions facilitated the release of H+ and regeneration of Fe(II). In addition, a plausible mechanism for enhanced Fenton-like degradation of DMP by phenolics was proposed.

3.
Water Res ; 168: 115164, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31629229

RESUMO

Carbamazepine (CBZ) is a typical pharmaceutical residue commonly found in aqueous environments, but its removal through activated carbon or advanced oxidation processes is often disrupted by co-existing organic matter. An imprinting system which consisted of the target pollutant CBZ (template molecule) and 10 different kinds of functional monomers was constructed via molecular simulation to screen for appropriate monomers, thereby addressing CBZ removal disruptions. An annealing method simulation was used to search for stable, low-energy conformations of the template-monomer interaction system to calculate the binding energy of these different monomers with CBZ. The order of binding affinity calculated was: 4-vinylbenzoic acid > itaconic acid > methacrylic acid, which was consistent with the experimental observations. The adsorption capacity of the molecular imprinted polymer (MIP) prepared using 4-vinylbenzoic acid reached 28.40 mg/g, and the imprinting factor reached 2.72. The simulation and measurement of the ultraviolet spectrum of the imprinting system showed that a new interaction system was formed between the template and monomers, and that multiple binding conformations between them took place when specific recognition occurred. Energy calculation and hydrogen bond analysis revealed that the van der Waals force, including the π-π conjugate and electrostatic forces including hydrogen bonding, played an important role during selective adsorption, which was confirmed by infrared spectroscopy analysis.


Assuntos
Poluentes Ambientais , Impressão Molecular , Preparações Farmacêuticas , Adsorção , Carbamazepina
4.
J Phys Condens Matter ; 32(5): 055001, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31604336

RESUMO

The exploration of new monolayer materials always attracts much attention due to the extraordinary properties and promising applications. Here we predict two monolayered aluminum triphosphides (AlP3) with C2/m and P3m1 space groups with a tunable bandgap under strain as the new members of the 2D XP3 family by using the first principles calculations. The stabilities of the predicted structures are confirmed with the phonon dispersion curves and molecular dynamics. Unlike the narrow bandgaps of the reported XP3 monolayers, the larger bandgaps of 1.78 (HSE06) or 1.91 eV (G0W0) for C2/m and 1.42 (HSE06) or 2.14 eV (G0W0) for P3m1 AlP3 monolayers are observed. The high mobility of 1.01 × 105 and 1.62 × 104 cm2 V-1 s-1 are observed for the electron of P3m1 and the hole of C2/m. The optical absorptions of the AlP3 monolayers, in particular, the one with C2/m, are obviously strong in the visible light range. These results imply that the monolayers are promising in the optoelectronic application. Unfortunately, the undesirable band edges make them not suitable for water splitting in spite of the strong optical absorption coefficient in the visible light range. However, an obvious effect of strain engineering is demonstrated for the monolayers. Under -2% and -3% biaxial strain, the band edges of P3m1 AlP3 can straddle the redox potential of water and meet the requirement of photocatalytic water splitting. Therefore, the P3m1 AlP3 monolayer can also be a promising candidate for the photocatalytic water splitting to produce hydrogen driven by the visible light.

5.
Mater Sci Eng C Mater Biol Appl ; 107: 110228, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761154

RESUMO

This study simulated the high-phosphorus (Pi) environment in patients with chronic kidney disease. Nano-hydroxyapatite (HAP) crystals were used to damage rat aortic smooth muscle cells (A7R5) pre-damaged with different concentrations of Pi solution to compare the differences in HAP-induced calcification in A7R5 cells before and after injury by high-Pi condition. After the A7R5 cells were damaged by high-Pi environment, the following were observed. HAP resulted in declined cell viability and lysosomal integrity, release of lactate dehydrogenase, and increased reactive oxygen species production. The ability of high-Pi damaged cells to internalize HAP crystals declined; crystal adhesion and calcium deposition on the cell surface and alkaline phosphatase activities increased. Osteopontin expression and level of Runt-related transcription factor 2 were increased, and HAP-induced osteogenic transformation was enhanced. High-Pi condition promoted the adhesion of A7R5 cells to nano-HAP crystals and inhibited HAP endocytosis, increasing the risk of calcification.

6.
J Nanosci Nanotechnol ; 20(3): 1838-1844, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492350

RESUMO

Pt/Bi2WO6 composite photocatalysts were prepared by a facile photoreduction method. Pt nanoparticles with an average size of 5-8 nm were successfully deposited on the surface of Bi2WO6 microspheres and the photocatalytic activity of Bi2WO6 was greatly improved by Pt nanoparticles. The photo-induced charge transfer properties of samples were studied by means of surface photovoltage (SPV) and transient photovoltage (TPV) techniques, giving an insight into the intrinsic reasons of the improvement in photocatalytic activity. The SPV and TPV results revealed that the deposited Pt nanoparticles could trap photo-induced electrons and then largely enhance the separation efficiency of photo-induced charge carriers.

7.
Acta Crystallogr D Struct Biol ; 75(Pt 12): 1138-1147, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31793907

RESUMO

The catalytic domain (residues 128-449) of the Orpinomyces sp. Y102 CelC7 enzyme (Orp CelC7) exhibits cellobiohydrolase and cellotriohydrolase activities. Crystal structures of Orp CelC7 and its cellobiose-bound complex have been solved at resolutions of 1.80 and 2.78 Å, respectively. Cellobiose occupies subsites +1 and +2 within the active site of Orp CelC7 and forms hydrogen bonds to two key residues: Asp248 and Asp409. Furthermore, its substrate-binding sites have both tunnel-like and open-cleft conformations, suggesting that the glycoside hydrolase family 6 (GH6) Orp CelC7 enzyme may perform enzymatic hydrolysis in the same way as endoglucanases and cellobiohydrolases. LC-MS/MS analysis revealed cellobiose (major) and cellotriose (minor) to be the respective products of endo and exo activity of the GH6 Orp CelC7.

8.
Environ Sci Technol ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31790212

RESUMO

Stability as evaluated by functional resistance and resilience is critical to the effective operation of environmental biotechnologies. To date, limited tools have been developed that allow operators of these technologies to predict functional responses to environmental and operational disturbances. In the present study, 17 Microbial Fuel Cells (MFCs) were exposed to a low pH perturbation. MFC power dropped 52.7 ± 35.8% during the low pH disturbance. Following the disturbance, 3 MFCs did not recover while 14 took 60.7 ± 58.3 hours to recover to previous current output levels. Machine learning models based on genomic data inputs were developed and evaluated on their ability to predict resistance and resilience. Resistance and resilience levels corresponding to risk of deactivation could be classified with 70.47 ± 15.88% and 65.33 ± 19.71 % accuracy, respectively. Models predicting resistance and resilience coefficient values projected post-perturbation current drops within 6.7 - 15.8% and recovery times within 5.8 - 8.7% of observed values. Results suggest that abundance of specific genera are better predictors of resistance while overall microbial community structure more accurately predicts resilience. This approach can be used to assess operational risk and is a first step towards further understanding and improving overall stability of environmental biotechnologies.

9.
Kidney Int ; 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31787254

RESUMO

Fibrosis is a common pathologic pathway of progressive kidney disease involving complex signaling networks. The deacetylase sirtuin 6 (sirt6) was recently implicated in kidney injury. However, it remains elusive whether and how sirt6 contributes to the regulation of kidney fibrosis. Here, we demonstrate that sirt6 protects against kidney interstitial fibrosis through epigenetic regulation of ß-catenin signaling. Sirt6 is markedly upregulated during fibrogenesis following obstructed nephropathy and kidney ischemia-reperfusion injury. Pharmacological inhibition of sirt6 deacetylase activity aggravates kidney fibrosis in obstructed nephropathy. Consistently, knockdown of sirt6 in mouse kidney proximal tubular epithelial cells aggravates transforming growth factor-ß-induced fibrosis in vitro. Mechanistically, sirt6 deficiency results in augmented expression of the downstream target proteins of ß-catenin signaling. We further show that sirt6 interacts with ß-catenin during transforming growth factor-ß treatment and binds to the promoters of ß-catenin target genes, resulting in the deacetylation of histone H3K56 to prevent the transcription of fibrosis-related genes. Thus, our data reveal the anti-fibrotic function of sirt6 by epigenetically attenuating ß-catenin target gene expression.

10.
J Therm Biol ; 86: 102448, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31789236

RESUMO

Human thermal adaptation is an important factor of indoor thermal comfort and energy conservation. To study the effect of indoor thermal history on cold adaptation in the early winter, climate chamber tests were conducted in cold environments at 16 °C with two different thermal experience groups. The groups are divided as follows: the natural ventilation (NV) group consisted of subjects living in naturally ventilated buildings (approximately 11.8 ±â€¯3.4 °C in winter (Liu, H., Wu, Y., Li, B., Cheng, Y., Yao, R., 2017. Seasonal variation of thermal sensations in residential buildings in the Hot Summer and Cold Winter zone of China. Energy and Buildings 140, 9-18)) and the air conditioning (AC) group consisted of subjects living in air-conditioned buildings for at least one year before the climate chamber experiments. The experiments on the NV and AC groups were conducted between December 1-13 and December 15-25, respectively. Each group consisted of 20 subjects wearing winter clothes (1.15 ±â€¯0.05 clo). The thermal sensation votes (TSVs) and thermal comfort votes (TCVs) in both groups were investigated and the subjects' skin temperatures were monitored during the experiments. The results showed that the mean TCV and TSV of both groups were not significantly different in the early winter. However, differences were observed in the subjects' localized body parts. The skin temperatures of the chest and arms of subjects in the NV group were higher than those in the AC group after exposure for 60 min at 16 °C, while calves skin temperatures of subjects in the NV group were lower. In addition, subjects in the AC group were found to feel colder compared to those in the NV group in cold environments at the same skin temperature. Thus, this study provides information about thermal comfort based on thermal experience in early winter.

11.
Molecules ; 24(23)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31795356

RESUMO

In this study, the aroma compounds of Huantai tartary buckwheat tea (TBH), three laboratory-produced scented tartary buckwheat teas, as well as the antioxidant activity of tea infusion was investigated. In total, 103 aroma components were isolated and identified from all samples. Tartary buckwheat rose tea (TBR) contained 57 aroma components and tartary buckwheat jasmine tea (TBJ) had 53, both of which were higher than those in others. In addition, the total flavonoid content (TFC) and the total phenolic content (TPC) of scented tartary buckwheat tea were much higher than those of TBH. After the tartary buckwheat tea (TBT) was soaked in hot water twice, the antioxidant activity of all samples decreased, and the antioxidant activity of TBR and TBJ infusions was more stable than those of others. Further, the antioxidant activity of the first tea infusion (FTI) of the TBT was higher than that of the second tea infusion (STI). Overall, considering the diverse aroma compounds of scented tartary buckwheat tea and higher antioxidant activity of tea infusions, the combination of scented tea and tartary buckwheat is a feasible approach to develop tartary buckwheat scented tea.

12.
J Mater Chem B ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31799596

RESUMO

To create a more precise, efficient imaging and therapeutic strategy is a big challenge for the current treatment of hepatocellular carcinoma (HCC). Photothermal therapy (PTT) has attracted enormous attention due to its non-invasive property and precise spatial and temporal control. Here, we developed a strategy to realize superior imaging performance and treatment, utilizing an indocyanine green (ICG) and sorafenib (S) co-loaded mesoporous silica nanosystem for synergetic PTT/immuno-enhanced therapy. We proved that (ICG+S)@mSiO2 could be easily endocytosed by H22 cells, carried out outstanding real-time fluorescence imaging, and enhanced cytotoxicity abilities by near-infrared radiation (NIR) in vitro. Moreover, (ICG+S)@mSiO2 also had excellent fluorescence imaging ability, displayed a remarkable photothermal tumor killing effect and immune enhancement capability under 808 nm irradiation in an H22 tumor-bearing mice model, without apparent adverse effects in other organs. This study provides a new strategy for the development of a PTT/immuno-enhanced synergistic theranostic nanosystem of HCC.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31802339

RESUMO

Based on the observed heavy metals in the Danshui River estuarine system, the concentration of manganese (Mn) exceeds the water quality standards. High concentrations of manganese in aquatic environment can cause disturbances in the sodium balance, disturb the metabolism of carbohydrates, and impair the immunological functions of fish. Therefore, a three-dimensional heavy metal transport model was developed and incorporated into the hydrodynamics, salinity, and suspended sediment transport model to evaluate the concentration distribution of the heavy metal manganese (Mn) in the Danshui River estuarine system of northern Taiwan. The model was validated with observational data for water level, tidal current, salinity, suspended sediment concentration, and heavy metal (Mn) concentration that was measured in 2015. The indicators of statistical error, including mean absolute error (MAE), root mean square error (RMSE), and skill score (SS), were adopted to evaluate the model performance. There was good quantitative agreement between the simulation results and measurements. Sensitivity analysis of suspended sediment and heavy metal transport model was carried out to understand which parameters were important to be cautiously determined. Furthermore, the validated model was used to investigate the influence of suspended sediment on the concentration distribution of heavy metals (Mn) in tidal estuaries. If the suspended sediment transport module was excluded in model simulations, the predicted results for the heavy metal (Mn) concentration underestimated the measured data. The modeling results showed that the inclusion of the suspended sediment transport module in the model simulations was critically important to the results of the heavy metal (Mn) concentration in the tidal estuarine system in Taiwan.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31702532

RESUMO

One aerobic, Gram-stain-negative, rod-shaped bacterium, designated strain RB1R5T, was isolated from Renlongba glacier in Tibet Autonomous Region, China. Growth was observed at 4-25 °C and pH 7.0-8.0. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain RB1R5T belongs to the genus Flavobacterium, and its closest relatives are Flavobacterium luteum IMCC26026T and Flavobacterium psychroterrae CCM 8827T with 97.75 and 97.42% gene sequence similarities, respectively. The average nucleotide identity and DNA-DNA hybridization values between strain RB1R5T and its closest relative Flavobacterium luteum IMCC26026T were 78.02 and 21.8 %, respectively. The major cellular fatty acids were anteiso-C15 : 0 and summed feature 3 (comprising C16:1ω7c/C16:1ω6c). The sole menaquinone was MK-6. The major phospholipid was phosphatidylethanolamine. On the basis of phenotypic, phylogenetic and chemotaxonomic characterizations, strain RB1R5T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium psychrotolerans sp. nov. is proposed. The type strain is RB1R5T (=CGMCC 1.23024T=NBRC 113060T).

15.
J Pediatr Orthop B ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31725535

RESUMO

Hip subluxation in ambulant children with cerebral palsy may lead to limited walking and pain. This study aimed to introduce the indications and methods of femoral varus osteotomy combined with Pemberton osteotomy in treating spastic hip subluxation to evaluate the interim clinical result and outcome and to discuss its corrective mechanism and orthopedic effect. A total of 23 children with spastic hip subluxation, who underwent femoral varus osteotomy combined with Pemberton osteotomy were selected. The clinical effects were evaluated according to the migration percentage, acetabular index, proximal femur neck shaft angle (NSA), and Melbourne Cerebral Palsy Hip Classification System (MCPHCS). The median migration percentage was 55 (50, 75) before operation, 20 (0, 30) at postoperative 1 year, and 22 (5, 32) at last follow-up. The median acetabular index was 30° (25°, 40°) before operation, 20°(15°, 26°) at postoperative 1 year, and 20° (15°, 25°) at last follow-up. The median NSA was 145 (138, 153) before operation, 117 (107, 126) at postoperative 1 year, and 118 (110, 125) at last follow-up. The MCPHCS grade 4 counts 23 (100%) before operation, grade 3 counts 20 (87.0%), grade 2 counts 2 (8.7%) and grade 1 counts 1 (4.3%) at postoperative 1 year, and grade 4 counts 1 (4.3%), grade3 counts 21 (91.3%) and grade 1 counts 1 (4.3%) at last follow-up. Femoral varus osteotomy combined with Pemberton osteotomy is a good surgical treatment for children with Gross Motor Function Classification System levels I and II and migration percentage greater than 50%.

16.
Medicine (Baltimore) ; 98(44): e17665, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689779

RESUMO

RATIONALE: Due to the rarity of bilateral cerebral peduncular infarction (BCPI), its symptoms and prognosis are not clear. It is necessary to collect cases of pure cerebral peduncular infarction, explore the etiology and anatomy of midbrain infarction in depth, and develop meaningful tools for explaining clinical symptoms and predicting prognosis of patients. PATIENT CONCERNS: We here provide a case of isolated BCPI with uncommon symptoms of ataxia, dysarthria, sensory disturbance, normal muscular strength, and full eye movements. DIAGNOSES: Diffusion weighted images and apparent diffusion coefficient map of our patient revealed acute and isolated bilateral peduncle cerebrum infarction. INTERVENTIONS: Drugs that could improve circulation and antiplatelet were used in therapy. OUTCOMES: The infarct size was enlarged and new infarction was identified in the splenium of the corpus callosum and pons. The patient developed progressed disorder of consciousness and died at the eleventh day. LESSONS: We inferred that the symptoms of ataxia, dysarthria, sensory disturbance, and mild paresis of the extremities could be prominent features of patients with pure cerebral peduncular infarction. We hypothesize that pure BCPI is also related to severe basilar artery stenosis or occlusion and there is no collateral circulation from PCA. This may explain the corresponding distribution of cerebral peduncular infarction and its poor prognosis. For these reasons, exploring etiology and anatomy of midbrain infarction in depth would have clinical value for predicting symptoms and prognosis.

17.
J Pharm Pharmacol ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31743450

RESUMO

OBJECTIVES: This study was aimed to explore the mechanism of Aconiti Lateralis Radix Praeparata (ALRP) and Zingiberis Rhizoma (ZR) on doxorubicin (DOX)-induced chronic heart failure (CHF) in rats by integrated approaches. METHODS: Effects of ALRP and ZR on cardiac function, serum biochemical indicators and histopathology in rats were analysed. Moreover, UHPLC-Q-TOF/MS was performed to identify the potential metabolites affecting the pathological process of CHF. Metabolomics and network pharmacology analyses were conducted to illustrate the possible pathways and network in CHF treatment. The predicted gene expression levels in heart tissue were verified and assessed by RT-PCR. KEY FINDINGS: ALRP-ZR demonstrated remarkable promotion of hemodynamic indices and alleviated histological damage of heart tissue. Metabolomics analyses showed that the therapeutic effect of ALRP and ZR is mainly associated with the regulation of eight metabolites and ten pathways, which may be responsible for the therapeutic efficacy of ALRP-ZR. Moreover, the results of RT-PCR showed that ALRP-ZR could substantially increase the expression level of energy metabolism-related genes, including PPARδ, PPARγ, Lpl, Scd, Fasn and Pla2g2e. CONCLUSIONS: The results highlighted the role of ALRP-ZR in the treatment of CHF by influencing the metabolites related to energy metabolism pathway via metabolomics and network pharmacology analyses.

18.
Artigo em Inglês | MEDLINE | ID: mdl-31745787

RESUMO

The essential oils (EOs) from aerial parts of Saussurea amara (L.) DC. (SAEO) and Sigesbeckia pubescens Makino (SPEO) were analyzed for their chemical composition by GC-MS, and their repellent activities against adults of the red flour beetle, Tribolium castaneum Herbst, as well as the booklouse, Liposcelis bostrychophila Badonnel, were evaluated for the first time. Results of GC-MS analysis indicated that both SAEO and SPEO were characterized by high content of sesquiterpenoids (relative content > 70%) including oxygenated sesquiterpenoids. The two oil samples and their major component caryophyllene oxide exerted beneficial repellent effects on T. castaneum and L. bostrychophila at 2 and 4 h post-exposure. At 4 h post-exposure, the PR value of caryophyllene oxide could still reach 92% (class V) against T. castaneum at minimum testing concentration of 3.15 nL/cm2, and this compound was observed to result in the greatest repellency (PR = 100%) against L. bostrychophila at 12.63 nL/cm2. This work confirmed the potent repellent efficacy of SAEO and SPEO for controlling pest damage and suggested their potential to be developed into botanical repellents.

19.
Int J Mol Med ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31746354

RESUMO

Senescence of cardiomyocytes is considered a key factor for the occurrence of doxorubicin (Dox)­associated cardiomyopathy. The NOD­like receptor family pyrin domain­containing 3 (NLRP3) inflammasome is reported to be involved in the process of cellular senescence. Furthermore, thioredoxin­interactive protein (TXNIP) is required for NLRP3 inflammasome activation and is considered to be a key component in the regulation of the pathogenesis of senescence. Studies have demonstrated that pretreatment with honokiol (Hnk) can alleviate Dox­induced cardiotoxicity. However, the impact of Hnk on cardiomyocyte senescence elicited by Dox and the underlying mechanisms remain unclear. The present study demonstrated that Hnk was able to prevent Dox­induced senescence of H9c2 cardiomyocytes, indicated by decreased senescence­associated ß­galactosidase (SA­ß­gal) staining, as well as decreased expression of p16INK4A and p21. Hnk also inhibited TXNIP expression and NLRP3 inflammasome activation in Dox­stimulated H9c2 cardiomyocytes. When TXNIP expression was enforced by adenovirus­mediated gene overexpression, the NLRP3 inflammasome was activated, which led to inhibition of the anti­inflammation and anti­senescence effects of Hnk on H9c2 cardiomyocytes under Dox treatment. Furthermore, adenovirus­mediated TXNIP­silencing inhibited the NLRP3 inflammasome. Consistently, TXNIP knockdown enhanced the anti­inflammation and anti­senescence effects of Hnk on H9c2 cardiomyocytes under Dox stimulation. In summary, Hnk was found to be effective in protecting cardiomyocytes against Dox­stimulated senescence. This protective effect was mediated via the inhibition of TXNIP expression and the subsequent suppression of the NLRP3 inflammasome. These results demonstrated that Hnk may be of value as a cardioprotective drug by inhibiting cardiomyocyte senescence.

20.
Small ; : e1904099, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31738003

RESUMO

Ever-growing tissue regeneration and other stem cell therapies cause pressing need for large population of self-renewable stem cells. However, stem cells gradually lose their stemness after long-term in vitro cultivation. In this study, a ZnO nanorod (ZnO NR) array is used to maintain the stemness of human adipose-derived stem cells (hADSCs). The results prove that after culturing hADSCs on ZnO NRs for 3 weeks, the stemness genes and protein expression level are higher than that on culture plates and ZnO film. ZnO NRs can maintain stemness of hADSCs without inhibiting the cell proliferation and oriented differentiation capabilities. KLF4 (Kruppel-like factor 4) is a Zn2+ -binding gene that plays a vital role in cell proliferation and differentiation. Sustained Zn2+ release and the increased expression of KLF4 can be detected, suggesting that ZnO NRs have efficiently released Zn2+ for stemness maintenance. Taken together, the nanotopography of ZnO NRs and the Zn2+ release synergistically facilitate stemness maintenance. This study has provided a powerful tool for directing cell fate, maintaining stemness, and realizing the expansion of stem cells in vitro, which will open a new route for the manufacture of large populations of stem cells and fulfilling the growing demand for the cell therapy market.

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