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1.
Nat Sci Sleep ; 16: 573-583, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38827393

RESUMEN

Purpose: This investigation sought to elucidate the genetic underpinnings that connect obesity indicators, circulating blood lipid levels, adipokines levels and obstructive sleep apnea syndrome (OSAS), employing a bidirectional two-sample Mendelian randomization (MR) analysis that utilizes data derived from extensive genome-wide association studies (GWAS). Methods: We harnessed genetic datasets of OSAS available from the FinnGen consortium and summary data of four obesity indices (including neck circumference), seven blood lipid (including triglycerides) and eleven adipokines (including leptin) from the IEU OpenGWAS database. We primarily utilized inverse variance weighted (IVW), weighted median, and MR-Egger methods, alongside MR-PRESSO and Cochran's Q tests, to validate and assess the diversity and heterogeneity of our findings. Results: After applying the Bonferroni correction, we identified significant correlations between OSAS and increased neck circumference (Odds Ratio [OR]: 3.472, 95% Confidence Interval [CI]: 1.954-6.169, P= 2.201E-05) and decreased high-density lipoprotein (HDL) cholesterol levels (OR: 0.904, 95% CI: 0.858-0.952, P= 1.251E-04). Concurrently, OSAS was linked to lower leptin levels (OR: 1.355, 95% CI: 1.069-1.718, P= 0.012) and leptin receptor levels (OR: 0.722, 95% CI: 0.530-0.996, P= 0.047). Sensitivity analyses revealed heterogeneity in HDL cholesterol and leptin indicators, but further multiplicative random effects IVW method analysis confirmed these correlations as significant (P< 0.05) without notable heterogeneity or horizontal pleiotropy in other instrumental variables. Conclusion: This investigation compellingly supports the hypothesis that OSAS could be a genetic predisposition for elevated neck circumference, dyslipidemia, and adipokine imbalance. These findings unveil potential genetic interactions between OSAS and metabolic syndrome, providing new pathways for research in this domain. Future investigations should aim to delineate the specific biological pathways by which OSAS impacts metabolic syndrome. Understanding these mechanisms is critical for developing targeted prevention and therapeutic strategies.

2.
Sci Rep ; 14(1): 8439, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600225

RESUMEN

This study presents a case of weakly consolidated strata developed in Dananhu No.7 coal mine. Using a combination of numerical simulation, field measurement comparison, and the critical hydraulic gradient criterion, we investigate the overburden failure and the risk possibility of water-sand mixture inrush during excavation. The following are the principal findings: (1) Weakly consolidated rocks have poor physical characteristics, particularly when they are mudded and disintegrated after encountering water, which may become a favorable source of water-sand inrush; (2) The water-conducting zone develops to a height of 160.5 m with a crack-mining ratio of 15.29 times, extending upward to Toutunhe Formation aquifer. The predictions are consistent with measurements in adjacent mines with similar geological conditions; (3) Cracks without larger subsidence are developed at the front edge of the mining direction, and some parallel stepped cracks behind the goaf could be easily observed. Ground subsidence along the goaf center finally displays a symmetrically wide-gentle U shape; (4) The critical hydraulic gradient of Toutunhe Formation aquifer, aquifer above 3# coal seam, and aquifer of 3#-7# coal seam in Xishanyao Formation is 1.314, 1.351, and 1.380, the actual value is 0.692, 2.089, and 7.418 accordingly. It is inferred water-sand mixture outburst will not occur in Toutunhe Formation aquifer, while the potential risk exists in the aquifers of Xishanyao Formation. Through drainage and depressurization projects, a water-sand mixture outburst accident does not occur during excavation. This study reveals the overburden failure characteristics and the initiation mechanism of water-sand inrush in weakly cemented strata, as well as the internal relationship between them, which provides new research ideas for safe operation in other mining areas with similar geological conditions. The research work has certain practical guiding significance.

3.
Antioxidants (Basel) ; 13(2)2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38397765

RESUMEN

This study aims to enhance gelatin film performance in the food industry by incorporating polyphenol-titanium complexes (PTCs) as crosslinkers. PTCs introduce multiple linkages with gelatin, including coordination and hydrogen bonds, resulting in synergistic crosslinking effects. This leads to an increased hydrodynamic volume, particle size, and thermal stability of the gelatin films. Compared to films crosslinked solely by polyphenols or titanium, PTC-crosslinked gelatin films exhibit significant improvements. They show enhanced mechanical properties with a tensile strength that is 1.7 to 2.6 times higher than neat gelatin films. Moreover, these films effectively shield UV light (from 82% to 99%), providing better protection for light-sensitive food ingredients and preserving lutein content (from 74.2% to 78.1%) under light exposure. The incorporation of PTCs also improves film hydrophobicity, as indicated by water contact angles ranging from 115.3° to 131.9° and a water solubility ranging from 31.5% to 33.6%. Additionally, PTC-enhanced films demonstrate a superior antioxidant ability, with a prolonged polyphenol release (up to 18 days in immersed water) and a higher free radical scavenging ability (from 22% to 25.2%). Overall, the improved characteristics of gelatin films enabled by PTCs enhance their performance, making them suitable for various food packaging applications.

4.
Int Immunopharmacol ; 126: 111234, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37977071

RESUMEN

Obstructive sleep apnea (OSA), a state of sleep disruption, is characterized by recurrent apnea, chronic intermittent hypoxia (CIH) and hypercapnia. Previous studies have showed that CIH-induced neuroinflammatory plays a crucial role in cognitive deficits. Pseudoginsenoside GQ (PGQ) is a new oxytetracycline-type saponin formed by the oxidation and cyclization of the 20(S) Rg3 side chain. Rg3 has been found to afford anti-inflammatory effects, while whether PGQ plays a role of anti-neuroinflammatory remains unclear. The purpose of this study was to investigate whether PGQ attenuates CIH-induced neuroinflammatory and cognitive impairment and the possible mechanism it involves. We found that PGQ significantly ameliorated CIH-induced spatial learning deficits, and inhibited microglial activation, pro-inflammatory cytokine release, and neuronal apoptosis in the hippocampus of CIH mice. In addition, PGQ pretreatment promoted microglial M1 to M2 phenotypic transition in IH-induced BV-2 microglial, as well as indirectly inhibited IH-induced neuronal injury via modulation of microglia polarization. Furthermore, we noted that activation of HMGB1/TLR4/NF-κB signaling pathway induced by IH was inhibited by PGQ. Molecular docking results revealed that PGQ could bind to the active sites of HMGB1 and TLR4. Taken together, this work supports that PGQ inhibits M1 microglial polarization via the HMGB1/TLR4/NF-κB signaling pathway, and indirectly exerts neuroprotective effects, suggesting that PGQ may be a potential therapeutic strategy for cognitive impairment accompanied OSA.


Asunto(s)
Proteína HMGB1 , Apnea Obstructiva del Sueño , Ratones , Animales , Microglía , FN-kappa B/metabolismo , Proteína HMGB1/metabolismo , Inflamación/tratamiento farmacológico , Receptor Toll-Like 4/metabolismo , Simulación del Acoplamiento Molecular , Hipoxia/metabolismo , Apnea Obstructiva del Sueño/metabolismo , Cognición
5.
Front Chem ; 11: 1260533, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37789965

RESUMEN

Four distinct fluorescence complexes, the fluorescent complex-1 (FC-1), fluorescent complex-2 (FC-2), fluorescent complex third (FC-3) and fluorescent complex fourth (FC-4), were created using isorhamnetin and Coomassie brilliant blue G250 as raw materials. The issue of isorhamnetin's low solubility has been resolved, and isorhamnetin-coomassie brilliant blue G250 now has better biocompatibility. Four different forms of fluorescence compounds' ultraviolet absorption spectra were identified. It was discovered that FC-2, FC-3, and FC-4, respectively, had double peaks at 483-620 nm. FC-4 had the highest ultraviolet absorption intensity, whereas FC-1 exhibited the most consistent and longest wavelength of ultraviolet absorption. Transmission electron microscopy revealed that the acrylic resin evenly disseminated the Coomassie brilliant blue G250-isorhamnetin complex in an amorphous flocculent form. Human prostate cancer cells (PC3) and human cervical cancer cells (HeLa) were investigated in the (Cell Counting Kit-8) CCK8 experiment under 10 different concentration circumstances, and the proliferation impact was 64.30% and 68.06%, respectively. Shown the complex's strong anti-tumor properties and minimal cytotoxicity. Through in vitro imaging of tumor cells, it was found that FC-1's fluorescent complex has high selectivity and can accurately infiltrate tumor cells, proving that it is biocompatible. The design not only addresses the issue of isorhamnein-Coomassie Bright Blue G250's bioavailability, but it also has an effective visual fluorescence targeting effect.

6.
Biomed Pharmacother ; 166: 115320, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37595427

RESUMEN

The COVID-19 pandemic has caused significant global impact, resulting in long-term health effects for many individuals. As more patients recover, there is a growing need to identify effective management strategies for ongoing health concerns, such as post-COVID-19 syndrome, characterized by persistent symptoms or complications beyond several weeks or months from the onset of symptoms. In this review, we explore the potential of dietary polysaccharides as a promising approach to managing post-COVID-19 syndrome. We summarize the immunomodulatory, antioxidant, antiviral, and prebiotic activities of dietary polysaccharides for the management of post-COVID-19 syndrome. Furthermore, the review investigates the role of polysaccharides in enhancing immune response, regulating immune function, improving oxidative stress, inhibiting virus binding to ACE2, balancing gut microbiota, and increasing functional metabolites. These properties of dietary polysaccharides may help alleviate COVID-19 symptoms, providing a promising avenue for effective treatment strategies.


Asunto(s)
COVID-19 , Humanos , Pandemias , Polisacáridos/uso terapéutico , Síndrome Post Agudo de COVID-19 , Antioxidantes/uso terapéutico , Carbohidratos de la Dieta
7.
Pharmaceuticals (Basel) ; 16(6)2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37375807

RESUMEN

The COVID-19 pandemic has had a profound impact worldwide, resulting in long-term health effects for many individuals. Recently, as more and more people recover from COVID-19, there is an increasing need to identify effective management strategies for post-COVID-19 syndrome, which may include diarrhea, fatigue, and chronic inflammation. Oligosaccharides derived from natural resources have been shown to have prebiotic effects, and emerging evidence suggests that they may also have immunomodulatory and anti-inflammatory effects, which could be particularly relevant in mitigating the long-term effects of COVID-19. In this review, we explore the potential of oligosaccharides as regulators of gut microbiota and intestinal health in post-COVID-19 management. We discuss the complex interactions between the gut microbiota, their functional metabolites, such as short-chain fatty acids, and the immune system, highlighting the potential of oligosaccharides to improve gut health and manage post-COVID-19 syndrome. Furthermore, we review evidence of gut microbiota with angiotensin-converting enzyme 2 expression for alleviating post-COVID-19 syndrome. Therefore, oligosaccharides offer a safe, natural, and effective approach to potentially improving gut microbiota, intestinal health, and overall health outcomes in post-COVID-19 management.

8.
J Agric Food Chem ; 71(19): 7299-7311, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37132503

RESUMEN

The pharmacological values of marine algal polysaccharides on gut health are being recognized in recent research. However, the protective effect of degraded polysaccharides from Porphyra haitanensis (PHP-D) on the colonic mucosal barrier damaged in ulcerative colitis is poorly understood. The purpose of this study was to investigate how PHP-D could maintain the integrity of colonic mucosal layer mediated by microbiota in a dextran sulfate sodium (DSS)-induced colitis mouse model. Structural analysis revealed that PHP-D had a typical porphyran structure having a backbone of alternating (1 → 3)-linked ß-d-galactopyranose units linked to either (1 → 4)-3,6-anhydro-α-l-galactopyranose units or (1 → 4)-linked α-l-galactose-6-sulfate units. An in vivo study demonstrated that PHP-D treatment reduced the severity of DSS-induced ulcerative colitis. 16S rRNA phylogenetic sequencing revealed that PHP-D affected the diversity of gut microbiota with an increase of Bacteroides, Muribaculum, and Lactobacillus species. Similarly, PHP-D increased levels of short-chain fatty acids. Furthermore, PHP-D restored mucus thickness and improved the expression of tight junction proteins. This work demonstrates that PHP-D is capable of enhancing a colonic mucosal barrier. These outcomes offer unique perspectives on the potential application of P. haitanensis as a promising natural product for the management of ulcerative colitis.


Asunto(s)
Colitis Ulcerosa , Colitis , Microbioma Gastrointestinal , Ratones , Animales , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/metabolismo , Sulfato de Dextran/metabolismo , Galactosa/metabolismo , ARN Ribosómico 16S/genética , Filogenia , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/metabolismo , Colon/metabolismo , Polisacáridos/metabolismo , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL
9.
Foods ; 12(5)2023 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-36900632

RESUMEN

Morchella esculenta is an edible mushroom with special flavor and high nutritional value for humans, primarily owing to its polysaccharide constituents. M. esculenta polysaccharides (MEPs) possess remarkable pharmaceutical properties, including antioxidant, anti-inflammatory, immunomodulatory, and anti-atherogenic activities. The aim of this study was to evaluate the in vitro and in vivo antioxidant potential of MEPs. In vitro activity was determined using free radical scavenging assays, whereas in vivo activity was evaluated through dextran sodium sulfate (DSS)-induced liver injury in mice with acute colitis. MEPs effectively scavenged 1,1-diphenyl-2-picrylhydrazyl and 2,2-azinobis-6-(3-ethylbenzothiazoline sulfonic acid) free radicals in a dose-dependent manner. Additionally, DSS-induced mice showed severe liver damage, cellular infiltration, tissue necrosis, and decreased antioxidant capacity. In contrast, intragastric administration of MEPs showed hepatoprotective effects against DSS-induced liver injury. MEPs remarkably elevated the expression levels of superoxide dismutase, glutathione peroxidase, and catalase. Additionally, it decreased malondialdehyde and myeloperoxidase levels in the liver. These results indicate that the protective effects of MEP against DSS-induced hepatic injury could rely on its ability to reduce oxidative stress, suppress inflammatory responses, and improve antioxidant enzyme activity in the liver. Therefore, MEPs could be explored as potential natural antioxidant agents in medicine or as functional foods to prevent liver injury.

10.
Oncol Lett ; 24(4): 342, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36072005

RESUMEN

[This retracts the article DOI: 10.3892/ol.2017.5709.].

11.
Dalton Trans ; 51(24): 9218-9222, 2022 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-35670316

RESUMEN

A C,S bonded quasi-two-coordinate Cr(II) complex, Cr(SAr*)2 (HSAr* = HSC6H3-2,6(C6H2-2,4,6-Pri3)2), has been synthesized according to literature precedent. Magnetic measurements, high-frequency/field electron paramagnetic resonance (HF-EPR) experiments and ab initio calculation studies show that the field-induced slow magnetic relaxation behaviour is caused by relatively weak axial magnetic anisotropy.

12.
Magn Reson Imaging ; 92: 260-267, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35623416

RESUMEN

PURPOSE: To determine the accuracy, repeatability, and reproducibility of magnetic resonance imaging-based proton density fat fraction (MRI-PDFF) measurements of rotator cuff muscles between two readers and three different scanners. METHODS: Twenty-seven volunteers underwent serial shoulder MRI examinations of both left and right sides on one 1.5-T MRI scanner and two 3.0-T MRI scanners. Two independent readers measured muscular PDFF of the supraspinatus, infraspinatus/teres minor muscle, and subscapularis. MR spectroscopy-based proton density fat fraction (MRS-PDFF) was regarded as the reference standard for assessing accuracy. A "coffee break" examination method was used to test the repeatability of each scanner. Bland-Altman plots, Pearson correlation, and linear regression analysis were used to assess bias and linearity. The Wilcoxon signed-rank test and Friedman test were applied to evaluate repeatability and reproducibility. RESULTS: MRI-PDFF measurements indicated strong linearity (R2 = 0.749) and small bias (-0.18%) in comparison with the MRS-PDFF measurements. A very strong positive Pearson correlation (r = 0.955-0.986) between the PDFF estimates of the two repeat scans indicated excellent repeatability. The PDFF measurements showed high reproducibility, with a strong positive Pearson correlation (r = 0.668-0.698) and a small mean bias (-0.04 to -0.10%) across different scanners. CONCLUSION: MRI-PDFF measurements of rotator cuff muscles were highly accurate, repeatable, and reproducible across different readers and scanners, leading us to the conclusion that PDFF can be a reliable and robust quantitative imaging biomarker for longitudinal or multi-center studies.


Asunto(s)
Protones , Manguito de los Rotadores , Humanos , Hígado/patología , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética/métodos , Reproducibilidad de los Resultados , Manguito de los Rotadores/diagnóstico por imagen
13.
Antioxidants (Basel) ; 11(4)2022 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35453457

RESUMEN

The application of hops could be extended to obtain higher commercial values. Tannins from hops were assessed for their tyrosinase inhibition ability, and the associated mechanisms were explored. Nuclear magnetic resonance (NMR) and high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS) revealed that the hop tannins were characterized as condensed tannins with (epi)catechin and (epi)gallocatechin as subunits and an average polymerization degree of 10.32. Tyrosinase inhibition assay indicated that hop tannins had an IC50 = 76.52 ± 6.56 µM. Kinetic studies of the inhibition processes indicated the tannins provided inhibition through competitive-uncompetitive mixed reactions. In silico molecule docking showed that tannins were bound to the active site of tyrosinase via hydrogen and electrovalent bonds. Circular dichroism (CD) observed the structural variation in the tyrosinase after reacting with the tannins. Fluorescence quenching analysis and free radical scavenging assays indicated that the tannins had copper ion chelating and antioxidant activities, which may also contribute to inhibition. The intracellular inhibition assay revealed that the melanin was reduced by 34.50% in B16F10 cells. These results indicate that these tannins can be applied as whitening agents in the cosmetics industry.

14.
Acta Pharmacol Sin ; 43(9): 2242-2252, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35169271

RESUMEN

Ghrelin is a circulating orexigenic hormone that promotes feeding behavior and regulates metabolism in humans and rodents. We previously reported that local infusion of ghrelin into the basolateral amygdala (BLA) blocked memory acquisition for conditioned taste aversion (CTA) by activating growth hormone secretagogue receptor 1a. In this study, we further explored the underlying mechanism and signaling pathways mediating ghrelin modulation of CTA memory in rats. Pharmacological agents targeting distinct signaling pathways were infused into the BLA during conditioning. We showed that preadministration of the PI3K inhibitor LY294002 abolished the repressive effect of ghrelin on CTA memory. Moreover, LY294002 pretreatment prevented ghrelin from inhibiting Arc and zif268 mRNA expression in the BLA triggered by CTA memory retrieval. Preadministration of rapamycin eliminated the repressive effect of ghrelin, while Gsk3 inhibitors failed to mimic ghrelin's effect. In addition, PLC and PKC inhibitors microinfused in the BLA blocked ghrelin's repression of CTA acquisition. These results demonstrate that ghrelin signaling in the BLA shapes CTA memory via the PI3K/Akt/mTOR and PLC/PKC pathways. We conducted in vivo multichannel recordings from mouse BLA neurons and found that microinjection of ghrelin (20 µM) suppressed intrinsic excitability. By means of whole-cell recordings from rat brain slices, we showed that bath application of ghrelin (200 nM) had no effect on basal synaptic transmission or synaptic plasticity of BLA pyramidal neurons. Together, this study reveals the mechanism underlying ghrelin-induced interference with CTA memory acquisition in rats, i.e., suppression of intrinsic excitability of BLA principal neurons via the PI3K/Akt/mTOR and PLC/PKC pathways.


Asunto(s)
Complejo Nuclear Basolateral , Amígdala del Cerebelo/fisiología , Animales , Reacción de Prevención , Complejo Nuclear Basolateral/fisiología , Conducta Alimentaria , Ghrelina/farmacología , Ghrelina/fisiología , Glucógeno Sintasa Quinasa 3/farmacología , Humanos , Ratones , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Ratas , Transducción de Señal , Serina-Treonina Quinasas TOR , Fosfolipasas de Tipo C/metabolismo
15.
Ear Nose Throat J ; 101(5): NP199-NP202, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32921173

RESUMEN

Basaloid squamous cell carcinoma and large cell neuroendocrine carcinoma are not common in head and neck, these tumors rarely occur in the larynx but both have highly aggressive clinical behavior and a high mortality rate. The diagnosis is complicated by these tumors' atypical clinical and pathological features. This case details a coexistence of basaloid squamous cell carcinoma and large cell neuroendocrine carcinoma of a woman in the larynx. The patient underwent endoscopy- and coblation-assisted transoral microsurgery to achieve hyoid horizontal epiglottidectomy and has no recurrence after 12 months of follow-up.


Asunto(s)
Carcinoma Neuroendocrino , Carcinoma de Células Escamosas , Laringe , Carcinoma Neuroendocrino/complicaciones , Carcinoma Neuroendocrino/diagnóstico , Carcinoma Neuroendocrino/cirugía , Carcinoma de Células Escamosas/complicaciones , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/cirugía , Femenino , Humanos , Laringe/patología
16.
Sheng Wu Gong Cheng Xue Bao ; 37(8): 2947-2955, 2021 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-34472311

RESUMEN

With improvements in information technology and expansion in education reforms, more innovative teaching reform programs have also been launched. Information technology has increased interest in the use of the flipped classroom innovative teaching model. In order to explore new ideas for the improvement of teaching, this paper focuses on the flipped classroom teaching approach with the integration of information technology. Micro-teaching is an important innovative flipped classroom teaching approach with a number of advantages as it is short, concise, and interesting, which therefore helps improve students' self-learning ability. Designing and preparing micro-teaching would become a prerequisite skill for college teachers. Based on the analysis of the entries in the "National Universities Micro-teaching Competition of Life Science", this paper explores the application of micro-teaching in life sciences teaching from the perspective of curriculum introduction, mode of presentation, teaching design, and other aspects of teaching. This information could serve as a guide to frontline college teachers to help them understand and master the skills of designing micro-teaching, so as to generate interest and improve learning efficiency among college students.


Asunto(s)
Disciplinas de las Ciencias Biológicas , Universidades , Curriculum , Humanos , Aprendizaje , Estudiantes
17.
J Phys Chem Lett ; 12(29): 6941-6945, 2021 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-34282915

RESUMEN

Supported Au catalysts efficiently catalyze the oxidative coupling of methanol with O2 to methyl formate, in which the atomic O species (O(a)) formed via O2 dissociation on the Au surface has been considered as the active oxygen species. Herein we report for the first time that the oxidative coupling of methanol can occur facilely with molecularly adsorbed O2 species (O2(a)) on a Au(997) surface at temperatures as low as around 125 K, while that with O(a) occurs at around 175 K. Both experimental and theoretical calculation results demonstrate a novel reaction mechanism of oxidative coupling of CH3OH with O2(a) via a dioxymethylene (H2COO) intermediate, resulting in the production of both HCOOCH3 and HCOOCH3. These results reveal the unique reactivity of molecularly adsorbed O2 species on Au surfaces for low-temperature oxidation reactions.

18.
Cancer Cell Int ; 21(1): 382, 2021 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-34281558

RESUMEN

BACKGROUND: Ginsenosides have been reported to possess a variety of biological activities. Synthesized from the ginsenoside protopanaxadiol (PPD), the octanone pseudoginsengenin DQ (PDQ) may have robust pharmacological effects as a secondary ginsenoside. Nevertheless, its antitumour activity and molecular mechanism against hypopharyngeal cancer cells remain unclear. METHODS: Cell Counting Kit8 assays, cell cycle assays and cell apoptosis assays were conducted to assess FaDu cell proliferation, cell phase and apoptosis. The interactions between PDQ and HIF-1α were investigated by a molecular docking study. The expression of HIF-1α, GLUT1, and apoptosis-related proteins was detected by Western blotting, direct stochastic optical reconstruction microscopy (dSTORM) and qRT-PCR. A glucose uptake assay was used to assess the glucose uptake capacity of FaDu cells. RESULTS: PDQ suppressed proliferation, reduced glucose uptake, and induced cell cycle arrest and apoptosis in FaDu cells. A molecular docking study demonstrated that PDQ could interact with the active site of HIF-1α. PDQ decreased the expression and mRNA levels of HIF-1α and its downstream factor GLUT1. Moreover, the dSTORM results showed that PDQ reduced GLUT1 expression on the cell membrane and inhibited GLUT1 clustering. CONCLUSION: Our work showed that the antitumour effect of PDQ was related to the downregulation of the HIF-1α-GLUT1 pathway, suggesting that PDQ could be a potential therapeutic agent for hypopharyngeal cancer treatment.

19.
Molecules ; 26(9)2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-34067030

RESUMEN

Valonea tannin is a natural product readily extracted from acorn shells that has been suggested to have potential skin whitening properties. This study investigated the tyrosinase inhibition activity of extracted valonea tannin and the associated structure-function activity. Nuclear magnetic resonance spectroscopy and molecular weight analysis with gel permeation chromatography revealed that valonea tannin could be characterized as a hydrolysable tannin with galloyl, hexahydroxydiphenoyl and open formed-glucose moieties and an average molecular weight of 3042 ± 15 Da. Tyrosinase inhibition assays demonstrated that valonea tannin was 334 times more effective than gallic acid and 3.4 times more effective than tannic acid, which may relate to the larger molecular size. Kinetic studies of the inhibition reactions indicated that valonea tannin provided tyrosinase inhibition through mixed competitive-uncompetitive way. Stern-Volmer fitted fluorescence quenching analysis, isothermal titration calorimetry analysis and in silico molecule docking showed valonea tannin non-selectively bound to the surface of tyrosinase via hydrogen bonds and hydrophobic interactions. Inductively coupled plasma-optical emission spectroscopy and free radical scavenging assays indicated the valonea tannin had copper ion chelating and antioxidant ability, which may also contribute to inhibition activity. These results demonstrated the structure-function activity of valonea tannin as a highly effective natural tyrosinase inhibitor that may have commercial application in dermatological medicines or cosmetic products.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Taninos Hidrolizables/química , Taninos Hidrolizables/farmacología , Monofenol Monooxigenasa/antagonistas & inhibidores , Antioxidantes/farmacología , Espectroscopía de Resonancia Magnética con Carbono-13 , Quelantes/farmacología , Cobre/aislamiento & purificación , Ácido Gálico/farmacología , Cinética , Ligandos , Simulación del Acoplamiento Molecular , Monofenol Monooxigenasa/metabolismo , Espectrometría de Fluorescencia , Taninos/farmacología , Termodinámica
20.
J Food Sci ; 86(7): 2978-2989, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34155646

RESUMEN

Passion fruit rind is a waste product from the beverage industry that is rich in anthocyanins that can be potentially applied as a natural colorant. However, the inherent instability of anthocyanins causes rapid discoloration. In this study, the cyanidin-3-glucoside (C-3-G) in passion fruit rind was extracted using 50% ethanol and converted into nonbleachable pigments by reaction with Oolong tea extracts and acetaldehyde. Reactions over 70 days formed high concentrations of stable nonbleachable pigments (3.07-6.68 absorbance unit [A.U.], in total) such as pyranoanthocyanins, as well as oligomeric and polymeric pigments with ethyl-linked bridges. In C-3-G and acetaldehyde reaction, positive relations were found among acetaldehyde concentration, color density, and nonbleachable pigment concentrations. As for reactions with C-3-G and Oolong tea extract combined with acetaldehyde, greater color density and greater concentrations of nonbleachable pigments (10.80-12.34, 4.25-4.40 A.U., respectively) were formed compared with acetaldehyde alone. In addition, the antioxidant capabilities of the extracts were enhanced after reaction with Oolong tea extracts. The results of this study show a useful method to enhance the stability of anthocyanins from passion fruit rind and also provide greater economic value to this waste product. PRACTICAL APPLICATION: Ripened passion fruits contain a high concentration of anthocyanins in their rind. These anthocyanins can be optimally extracted by ultrasonic assisted solvent extraction to provide stable pigments by inducing acetaldehyde (a volatile compound often found in foods and beverages) into the anthocyanins. These stable pigments have a greater reddish hue in solution than the anthocyanin extracted from the rind and are more stable over a greater pH range. In addition, these stable pigments can be potentially used as colorant throughout the food and cosmetic industry to provide high economical values.


Asunto(s)
Antocianinas/química , Colorantes/química , Passiflora/química , Extractos Vegetales/química , Acetaldehído , Antocianinas/aislamiento & purificación , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Colorantes/aislamiento & purificación , Frutas/química , Extractos Vegetales/aislamiento & purificación
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