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1.
Behav Brain Res ; 378: 112278, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31629836

RESUMO

Stroke leads to devastating outcomes including impairments of sensorimotor and cognitive function that may be long lasting. New intervention strategies are needed to overcome the long-lasting effects of ischemic injury. Previous studies determined that treatment with 5-methoxyindole-2-carboxylic acid (MICA) conferred chemical preconditioning and neuroprotection against stroke. The purpose of the current study was to determine whether the preconditioning can lead to functional improvements after stroke (done by transient middle cerebral artery occlusion). After 4 weeks of MICA feeding, half the rats underwent ischemic injury, while the other half remained intact. After one week recovery, all the rats were tested for motor and cognitive function (rotorod and water maze). At the time of euthanasia, measurements of long-term potentiation (LTP) were performed. While stroke injury led to motor and cognitive dysfunction, MICA supplementation did not reverse these impairments. However, MICA supplementation did improve stroke-related impairments in hippocampal LTP. The dichotomy of the outcomes suggest that more studies are needed to determine optimum duration and dosage for MICA to lead to substantial motor and cognitive improvements, along with LTP change and neuroprotection.

2.
Neurosci Lett ; : 134657, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31785307

RESUMO

Mesencephalic astrocyte-derived neurotrophic factor (MANF) is an endoplasmic reticulum stress-related protein that exhibits neuroprotective effects. Recent studies have shown that MANF promotes poststroke functional recovery in rats. However, the underlying mechanisms have not yet been fully understood. Here, we examined the effects of MANF on cerebral angiogenesis in a permanent middle cerebral artery occlusion model in rats. Recombinant human MANF was administered intracerebroventricularly 24 h after stroke. We performed neurobehavioral tests and assessed microvessel density, functional microvessels, and regional cerebral blood flow (rCBF), as well as detected angiogenic factors in the peri-infarct cerebral cortex. Results showed that MANF ameliorated neurobehavioral scores, promoted rCBF, upregulated the expression of CD34, as well as the total vessel surface area and the number of microvessel branch points, and activated the vascular endothelial growth factor (VEGF) pathway. In conclusion, our findings provide insight into the mechanisms of MANF in promoting functional recovery from ischemic stroke. Our results suggest that MANF improves neurobehavioral recovery from cerebral ischemic injury, and that this effect is mediated partly by its proangiogenic effects and augmentation of rCBF, which are possibly associated with VEGF.

3.
Medicine (Baltimore) ; 98(49): e18245, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31804352

RESUMO

BACKGROUND: Optimal glycemic control is required to restrain the increase of cardiovascular events in patients with type 2 diabetes. The effects of sodium-glucose cotransporter-2 (SGLT-2) inhibitors on cardiovascular events and mortality in those patients are not well established. This meta-analysis was conducted to assess the effects of SGLT2 inhibitors on cardiovascular events and mortality in patients with type 2 diabetes. METHODS: We conducted a systematic literature search of Medline, Embase and Cochrane Library and included randomized controlled trials (RCTs) of 3 different SGLT2 inhibitors (canagliflozin, dapagliflozin and empagliflozin) that evaluated the effects on cardiovascular outcomes and mortality in the final meta-analysis. The intervention arm was defined either as SGLT2 inhibitor monotherapy or as SGLT2 inhibitor add-on to other non-SGLT2 inhibitor antidiabetic agents (ADAs). RESULTS: Forty-two trials with a total of 61,076 patients with type 2 diabetes were included in the meta-analysis. Compared with the control, SGLT2 inhibitor treatment was associated with a reduction in the incidence of major adverse cardiovascular events (MACEs) (OR = 0.86, 95% CI 0.80-0.93, P < .0001), myocardial infarction (OR = 0.86, 95% CI 0.79-0.94, P = .001), cardiovascular mortality (OR = 0.74, 95% CI 0.67-0.81, P < .0001) and all cause mortality (OR = 0.85, 95% CI 0.79-0.92, P < .0001). However, the risk of ischemic stroke was not reduced after SGLT2 inhibitor treatment in patients with type 2 diabetes (OR = 0.95, 95% CI 0.85-1.07, P = .42). CONCLUSION: These data suggest a decreased risk of harm with SGLT2 inhibitor as a class with respect to cardiovascular events and mortality.

4.
Mikrochim Acta ; 186(12): 765, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31713694

RESUMO

An enzyme-free fluorometric assay is described for the determination of zearalenone (ZEN). The method combines (a) catalyzed hairpin assembly (CHA), (b) ultrahigh fluorescent light-up G-rich DNA sequences in proximity to silver nanoclusters (Ag NCs), and (c) the use of aptamers (Apt). In the presence of ZEN, the inhibit sequence (Inh) is released from the aptamer-trigger sequence (Apt-T) via the binding of ZEN and the aptamer of Apt-T. The free Apt-T acts as a switch that opens the hairpins H1 and H2 to generate H1-H2 complex. The released Apt-T is available to trigger the next round of CHA between H1 and H2. Finally, the hybridization between H1 and the Ag NCs probe (P) causes the G-rich sequence to be in close proximity to the dark Ag NCs encapsulated by P. This leads to highly efficient lighting up of the Ag NCs and the production of amplified fluorescence with excitation/emission peaks at 575/628 nm. Under the optimized conditions, a linear correlation was observed with concentrations ranging from 1.3 pg mL-1 to 100 ng mL-1, and the limit of detection was 0.32 pg mL-1 (at S/N = 3). The method was successfully validated by analyzing maize and beer for levels of ZEN after a simple sample preparation procedure. Graphical abstractSchematic of the assay. The inhibit sequence (Inh) is released from aptamer-trigger sequence (Apt-T) via binding of ZEN and aptamer. The free Apt-T triggers catalyzed hairpin assembly (CHA).G-rich DNA is in proximity to silver nanoclusters (Ag NCs) and fluorescence intensity increases to detect ZEN.

5.
J Clin Lab Anal ; : e23112, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31733013

RESUMO

BACKGROUND: In patients with type 2 diabetes mellitus (T2DM), higher risks of impaired bone metabolism are widely reported. To evaluate bone metabolism, bone mineral density (BMD) and bone turnover levels should be included. In this article, we analyzed the relationship between them in T2DM. METHODS: We conducted a hospital-based cross-sectional study enrolling 1499 patients hospitalized for T2DM between October 2009 and January 2013. Multivariate linear regression models were used to identify the relationship between bone turnover markers (BTMs) and BMD levels. A two-sided P-value < .05 was considered statistically significant. RESULTS: After adjusting for confounding factors, osteocalcin (OC) showed a negative relationship with total lumbar, femur neck, and total hip BMD in men and women. N-terminal propeptides of type I collagen (P1NP) and alkaline phosphatase (ALP) showed a negative association with BMD at three sites in men and total lumbar BMD in women, whereas in the femur neck and total hip in women, the relationship was only found for P1NP with total hip. For ß-C-terminal telopeptides of type I collagen (ß-CTX), a negative relationship was also found in all three sites for BMD in men and total lumbar BMD in women, whereas ß-CTX was not associated in the femoral neck and total hip in women. CONCLUSION: In patients with T2DM, serum levels of OC, P1NP, ß-CTX, and ALP were negatively correlated with BMD levels in men in three sites and with total lumbar BMD in women. The relationship varied in femur neck and total hip BMD in women.

6.
J Mater Sci Mater Med ; 30(11): 123, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31686219

RESUMO

Prognosis and treatment evaluation of spinal cord injury (SCI) are still in the long-term research stage. Prognostic factors for SCI treatment need effective biomarker to assess therapeutic effect. Quantitative diffusion tensor imaging (DTI) may become a potential indicators for assessing SCI repair. However, its correlation with the results of locomotor function recovery and tissue repair has not been carefully studied. The aim of this study was to use quantitative DTI to predict neurological repair of SCI with transplanting collagen/chitosan scaffold binding basic fibroblast growth factor (bFGF). To achieve our research goals, T10 complete transection SCI model was established. Then collagen/chitosan mixture adsorbed with bFGF (CCS/bFGF) were implanted into rats with SCI. At 8 weeks after modeling, implanting CCS/bFGF demonstrated more significant improvements in locomotor function according to Basso-Beattie-Bresnahan (BBB) score, inclined-grid climbing test, and electrophysiological examinations. DTI was carried out to evaluate the repair of axons by diffusion tensor tractgraphy (DTT), fractional anisotropy (FA) and apparent diffusion coefficient (ADC), a numerical measure of relative white matter from the rostral to the caudal. Parallel to locomotor function recovery, the CCS/bFGF group could significantly promote the regeneration of nerve fibers tracts according to DTT, magnetic resonance imaging (MRI), Bielschowsky's silver staining and immunofluorescence staining. Positive correlations between imaging and locomotor function or histology were found at all locations from the rostral to the caudal (P < 0.0001). These results demonstrated that DTI might be used as an effective predictor for evaluating neurological repair after SCI in experimental trails and clinical cases.

8.
Theranostics ; 9(26): 8253-8265, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31754394

RESUMO

Rationale: Although mesenchymal stem cell (MSC) transplantation has been proved to be an effective therapeutic approach to treat experimental Sjögren's syndrome (SS), the detailed underlying mechanisms remains unknown. IL-27 has diverse influences on the regulation of T cell differentiation and was involved in SS through modulating immune response. Here we aimed to explore whether IL-27-mediated regulation of immune cells was responsible for the beneficial effects of MSC transplantation on SS. Methods: The SS-like symptoms were evaluated in IL-27 deficient and recombinant IL-27-treated NOD mice. The MSCs were infused into NOD mice via the tail vein. The histological features of submandibular glands, saliva flow rate and serum IL-27 were examined. The effects of MSCs on the IL-27 production and Th17/Treg cell in SS patients and mice in vitro and in vivo were determined for the mechanistic study. Results: This study showed that SS patients had decreased IL-27 level and increased ratio of Th17/Treg cells. Consistently, exacerbated SS-like symptoms were observed in IL-27 deficient NOD mice, along with increased ratio of Th17/Treg cells. Importantly, MSC transplantation alleviated SS-like symptoms by elevating the level of IL-27 to restore Th17/Treg balance in NOD mice. Mechanistically, MSC-secreted interferon-ß (IFN-ß) promote dendritic cells to produce IL-27. Conclusions: Thus, we have revealed a previously unrecognized function of MSC-mediated IL-27 production by DCs in suppressing SS-like syndrome, which provided evidences for clinical application of MSC in patients with SS.

9.
Molecules ; 24(23)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31766469

RESUMO

Nowadays, the analysis of the multi-components in Chinese patent medicine prescriptions is being paid more attention. Therefore, in this study for the first time, a simple, rapid ultrahigh performance liquid chromatography-electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS) method was established for simultaneous determination of 18 active compounds in a Chinese patent medicine of Hu Gan tablets (HGT) from different pharmaceutical factories in China. This task has met great emerging challenges from not only structural complexities and similarities but also co-occurrence of water-soluble and fat-soluble components in HGT. UPLC-ESI-MS/MS was put forward to solve the problems. It was operated in both positive and negative mode using multiple reaction monitoring (MRM). The mobile phase was 0.1% formic acid in water (A) -0.1% formic acid in acetonitrile (B) with linear gradient elution at a flow rate of 0.2 mL/min, run for a total of 12.0 min. The optimized method used provided short analysis time and good linearity (R2 > 0.99), and intra- and inter-day precision (relative standard deviation (RSD) < 4.00%) with good accuracy (94.89-110.03%) and recovery (70.00-126.09%). The results indicate the method could be practically used for quality guarantee of HGT and might also be useful for further studies.

10.
Colloids Surf B Biointerfaces ; : 110645, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31759777

RESUMO

Poly(vinyl alcohol) (PVA) hydrogels have been extensively studied as drug delivery systems. However, due to the high hydrophilicity of PVA, these hydrogels have weak abilities to efficiently load drugs and control the initial burst release. In this study, we present a one-step simple and rapid single needle electrospraying (SNESy) method that combines PVA hydrogels with another biocompatible polymer polycaprolactone (PCL). A distinct core-shell structure was obtained with the PVA hydrogel core and PCL shell after the system was properly set up. The results revealed that the volume ratio between PVA hydrogel and PCL played an important role in determining the particle size and the formation of a spherical structure. The double-walled structure of the microsphere was confirmed by taking the fluorescent images and conducting the ATR-FTIR method. Furthermore, doxorubicin hydrochloride was used as a model drug to evaluate the drug loading capacity and the in vitro release behavior of this PVA hydrogel/PCL microsphere. The results indicated that coating a layer of PCL polymer significantly enhanced the drug loading capacity and reduced the drug initial burst release compared to the single-layer PVA hydrogel nanoparticles, demonstrating these biocompatible double-walled microspheres can be applied as excellent drug delivery carriers.

11.
Chem Commun (Camb) ; 55(84): 12639-12642, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31580339

RESUMO

Polyubiquitination with diverse linkages on histones provides another layer of accuracy and complexity for epigenetic regulation, which is rarely studied. Herein, K27 or K48-diubiquitin modified H2A analogues were chemically synthesized using thiirane linkers. These permitted in vitro binding studies suggested the plasticity of ubiquitin chains in 53BP1 recognition.

12.
J Pharm Biomed Anal ; 178: 112898, 2019 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-31606564

RESUMO

A generic strategy based on chemical fingerprinting is proposed for the differentiation of polysaccharides from Astragalus membranaceus (AEP) and A. mongholicus (AOP), using multiple chromatographic and mass spectrometric techniques. Complete and mild acid hydrolysis and Smith degradation were employed for the depolymerization of polysaccharides. The corresponding digested products were efficiently separated and detected using GC-MS, HILIC-ELSD and HR-ESI--MS. The resulting bottom-up fingerprinting reflected the variations in native polysaccharides, which may be attributed to the three structural levels, which are monosaccharide compositions, glycosidic linkages, and skeletal structure. Similarity analysis from GC-MS and HILIC-ELSD fingerprinting showed that the correlation coefficients from homologous species were more than 0.914, whereas those from heterologous species were less than 0.796. It also noted that characteristic peak area ratio of Man/Gal in Smith fingerprinting could be used a feasible parameter for direct discrimination of AEP and AOP. Principal component analysis from m/z fingerprinting data resulted in clear clustering of AEP and AOP based on changes of oligosaccharides in mild acid hydrolyzates. By combining the accurate m/z, ESI--MS/MS and methylation assays, the structures of a series of hexose glycopolymers in mild acid hydrolyzates were characterized by predominant 1,6 glycosidic linkages along with minor 1,4 glycosidic linkages. The established chemical fingerprinting is not only an interconnected structure mapping but also a powerful approach for the evaluation of polysaccharides from traditional Chinese medicines.

13.
Nan Fang Yi Ke Da Xue Xue Bao ; 39(9): 1065-1070, 2019 Sep 30.
Artigo em Chinês | MEDLINE | ID: mdl-31640948

RESUMO

OBJECTIVE: To isolate tumor stem-like cells from human epithelial ovarian cancer SKOV3 cells and explore their role in the formation of vascularization mimicry (VM). METHODS: SKOV3 cells were passaged to the 7th generation by suspension culture in serum-free medium, and the percentages of CD133- and CD117-positive cells in the 1st, 3rd, 5th and 7th generations were analyzed using flow cytometry. The proliferative activity of the cells sorted from the 7th generation SKOV3 cells was assessed with colony formation assay. A three-dimensional cell culture model was established to compare the ability of VM formation between the sorted cells and the parental SKOV3 cells. The expression levels of matrix metalloproteinases-2 (MMP-2) and MMP-9 in the two groups were detected using real-time PCR and Western blotting. RESULTS: Some SKOV3 cells formed typical cell spheres with suspension growth in serum-free medium and were passaged to the 7th generation. Flow cytometry revealed that the percentage of CD133-positive cells increased with cell passaging. The cloning efficiency of the sorted cells was significantly higher than that of the parental SKOV3 cells (50.33% vs 5.33%, P < 0.001). The VM formation ability of the sorted cells was stronger than that of the parental SKOV3 cells in the three-dimensional cell culture system. RT-PCR and Western blotting showed that the expression levels of MMP-2 and MMP-9 were significantly higher in the 7th passage cells than in the parental cells (P < 0.05). CONCLUSIONS: The sorted cells from SKOV3 cells cultured in serum-free medium exhibit biological properties of tumor stem cells with strong VM formation ability, suggesting their role in VM formation.


Assuntos
Carcinoma Epitelial do Ovário/patologia , Células-Tronco Neoplásicas/citologia , Neovascularização Patológica/patologia , Neoplasias Ovarianas/patologia , Linhagem Celular Tumoral , Movimento Celular , Feminino , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo
14.
J Surg Res ; 246: 284-291, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31622885

RESUMO

BACKGROUND: Platelet-rich plasma (PRP) improves the healing of refractory wounds, and its application is receiving more attention in the field of wound repair. However, when a patient's condition is very poor, it may be difficult to provide whole blood to harvest autologous PRP. METHODS: We evaluated the efficacy and safety of allogeneic PRP in the field of chronic refractory wound repair. Sixty patients (39 males and 21 females, 57 ± 10 y old) with chronic wounds were enrolled in this prospective, randomized, single-center study during January 2014 to January 2018. Their wounds were treated by standard care. The patients with chronic refractory wounds were divided into allogeneic PRP treatment and control groups on the basis of the presence or absence of allogeneic PRP in wounds after debridement, respectively. Allogeneic PRP was prepared by collecting whole blood from healthy individuals and two-step centrifugation. Clinical effects were evaluated by visually observing wound conditions and objectively assessing wound surfaces. RESULTS: After 30 d of treatment, the allogeneic PRP-treated group showed bright red granulation that bled easily with reduced inflammatory exudation. No rejection reactions were observed. The rate of chronic wound healing was much faster in the allogeneic PRP-treated group than that in the control group. CONCLUSIONS: The present study shows that combined treatment of chronic wounds by standard care and allogeneic PRP significantly shortens healing time, suggesting that allogeneic PRP is an effective, safe adjuvant treatment for chronic wounds.

15.
Cell Death Dis ; 10(10): 755, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31591388

RESUMO

Ferroptosis is a non-apoptotic form of cell death characterized by the iron-dependent lipid peroxidation and is implicated in several human pathologies, such as tissue ischemia, neurodegeneration, and cancer. Ferroptosis appears to be high cell-context dependent and the regulation of ferroptosis by physiological or pathological conditions are unclear. Here, we report that tumor-derived IDH1 mutation sensitizes cells to ferroptosis. Deletion of the mutant IDH1 allele in IDH1 heterozygous tumor cells or pharmacological inhibition of mutant IDH1 to produce the oncometabolite D-2-hydroxyglutarate (D-2-HG) confers resistance to erastin-induced ferroptosis. Conversely, ectopic expression of mutant IDH1 or treatment of cells with cell-permeable D-2-HG promotes the accumulation of lipid reactive oxygen species (ROS) and subsequently ferroptosis. Mechanistically, mutant IDH1 reduces the protein level of the glutathione peroxidase 4 (GPX4), a key enzyme in removing lipid ROS and ferroptosis, and promotes depletion of glutathione. Our results uncover a new role of mutant IDH1 and 2-HG in ferroptosis.

16.
J Sci Food Agric ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31646634

RESUMO

The Tilapia collagen peptides mixture TY001 is effective in promoting wound healing in acetic acid-induced skin lesions in Zebrafish and in protecting against lipopolysaccharide-induced inflammation and disrupt of glucose metabolism in mice. The goal of the present study is to further examine the wound healing effects of TY001 in streptozotocin-induced diabetic mice. Full-thickness skin excision wounds were created with 8-mm biopsy punches and TY001 was administered via the drinking water (15, 30, and 45 g/L in emulsion) for 15 days. Wound healing was delayed in diabetic mice but was promoted by TY001 after 5, 10, or 15 days of treatment. Collagen deposition and tissue hydroxyproline contents were increased by TY001. The expressions of insulin growth factor-1, basic fibroblast growth factor, platelet-derived growth factor, transforming growth facts ß1, vascular endothelial growth factor, and epidermal growth factor were increased by TY001 as evidenced by immunobiochemistry and qPCR. Diabetes-associated serum pro-inflammatory cytokines IL-1ß and IL-8 were decreased, while anti-inflammatory IL-10 and nitric oxide were increased by TY001, along with increased tissue antioxidant superoxide dismutase and catalase activities. Diabetes-reduced serum protein levels were also recovered by TY001. Taken together, Tilapia collagen peptide mixture TY001 was effective in enhancing diabetes-associated wound healing delay, probably via increasing growth factors and collagen deposition in the wound, attenuating diabetes-induced prolonged inflammation, increasing tissue antioxidants, and providing nutritional supports in diabetic mice. This article is protected by copyright. All rights reserved.

17.
BMC Surg ; 19(1): 147, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31640661

RESUMO

BACKGROUND: We aimed to determine the optimal bipolar electrocoagulation power for laparoscopic surgery and to investigate which method, bipolar electrocoagulation, advanced bipolar, or ultrasonic technique was more reliable. METHODS: Goat mesenteric vessels (210 in vivo samples) with diameters of 3.03-5.44 mm were selected. Bipolar electrocoagulation with 80 W, 75 W, 70 W, 65 W, 60 W, 55 W, and 50 W, and advanced bipolar and ultrasonic techniques were performed on mesenteric vessels. The thermal damage width, hemostatic effect, and burst pressure of these tissues were recorded. SPSS version 13.0 was used for all data analysis. RESULTS: The results showed that 60 W was the optimal for bipolar electrocoagulation based on the thermal damage width, hemostatic effect, and burst pressure. In contrast, the thermal damage width of advanced bipolar and ultrasonic techniques was smaller than that of bipolar electrocoagulation, and advanced bipolartechnique had the highest successful rate for hemostasis and highest burst pressure. CONCLUSIONS: Bipolar electrocoagulation was optimally performed with 60 W of power. Compared with ultrasonic and bipolar electrocoagulation techniques, advanced bipolar use was more reliable for mesenteric vessels in laparoscopic surgery; however, bipolar electrocoagulation with optimal power can be used for its simplicity of operation and low cost.

18.
Dalton Trans ; 48(42): 15849-15855, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31602450

RESUMO

The most contracted cerium(iv)-based metal-organic framework (MOF) with fcu topology incorporating an alkyne-based linker, namely acetylenedicarboxylate (ADC), was synthesized under green conditions in water at room temperature and thoroughly characterized. The structure of this new MOF, denoted as Ce-HHU-1, was determined from powder X-ray diffraction data and Rietveld refinement and is made up of octahedral [Ce6O4(OH)4]12+ clusters, each of which is connected to other inorganic units by twelve ADC linkers to give a porous network with fcu topology analogous with UiO-66. The permanent microporosity of Ce-HHU-1 was confirmed by nitrogen sorption, meanwhile its high hydrophilicity was displayed by a type I water vapor sorption isotherm. The adsorption of CO2 in Ce-HHU-1 features a remarkably high zero-coverage isosteric heat of adsorption of 47 kJ mol-1, attributed to the presence of the -C[triple bond, length as m-dash]C- triple-bond in the framework. The latter also allows for Ce-HHU-1 to capture and irreversibly chemisorb Br2 vapors, as well as both chemi- and physisorb I2 vapors in an effective manner, making this material potentially applicable for air cleaning from toxic halogen vapors.

19.
Molecules ; 24(20)2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31623176

RESUMO

Resistance to anti-cancer drugs is one of the main factors of treatment failure resulting in high morbidity. Among the reasons of resistance, overexpression of efflux pumps leading to multidrug resistance is an important issue that needs to be solved. Taiwanofungus camphoratus has been used as a nutritional supplement to treat various cancers. However, its effects on the resistance to chemotherapeutic agents are still unknown. In this study, we report four new chemical constituents of T. camphoratus isolated from an ether extract: camphoratins K (1) and N (2) and benzocamphorins G (3) and I (4). Furthermore, we evaluated zhankuic acids A-C for their P-glycoprotein (P-gp) inhibitory effects. The results showed that zhankuic acid A was the most potent P-gp inhibitor compound and (at 20 µM) could reverse drug resistance in human cancer cells, restoring an IC50 of 78.5 nM for doxorubicin, of 48.5 nM for paclitaxel, and of 321.5 nM for vincristine, indicating a reversal fold of 48, 38, and 45 times, respectively. This study provides support for the use of T. camphoratus in the further development of cancer therapy.

20.
Org Biomol Chem ; 17(43): 9510-9513, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31657418

RESUMO

Nucleophilic addition of Grignard reagents to tetrahydro-ß-carboline (THC) N-sulfonyl N,S-acetal generates exclusively cis-1,3-disubstituted THCs with a unique 1,3-diaxial conformation. The stereochemical relationship of the 1,3-substituents was confirmed by 2-dimensional NMR spectroscopy and X-ray crystallography. The mechanism of the reaction is proposed based on crystal structures and molecular orbital calculations.

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