A novel nonenzymatic ascorbic acid electrochemical sensor based on gold nanoparticals-chicken egg white-copper phosphate-graphene oxide hybrid nanoflowers.

Au-CEW-Cu3(PO4)2-GO nanoflowers (HNFs), which were assembled of gold nanoparticals (Au NPs), chicken egg white (CEW), copper phosphate (Cu3(PO4)2) and graphene oxide (GO) together to form a flower-like organic/inorganic hybrid nanocomposite, were synthesized through a simple and gentle one-pot co-precipitation method. The prepared samples were well characterized by scanning electron microscope, transmission electron microscope, energy dispersive x-ray spectrometer, x-ray diffraction and Raman spectrometer. The prepared Au-CEW-Cu3(PO4)2-GO HNFs was used to modify glassy carbon electrode to fabricate an electrochemical sensor for detection of ascorbic acid (AA). The electrochemical test results show that the linear range of the developed sensor is 8-300µM and the detection limit is 2.67µM (S/N = 3). While this sensor displays high sensitivity of 6.01 × 10-3µAµM-1cm-2and low detection potential of 35 mV due to the combination of the high conductivity of Au NPs, the larger specific surface area of GO and the intrinsic electrocatalytic activity of CEW-Cu3(PO4)2HNFs. Moreover, the Au-CEW-Cu3(PO4)2-GO HNFs-based sensor was successfully developed for application in electrochemical detection of AA in vitamin C tablets.

[Association of RAGE gene polymorphisms with MHR ratio and heart rate variability among patients with coronary heart disease].

OBJECTIVE: To assess the association of polymorphisms of receptor of advanced glycation end products (RAGE) gene, monocyte to high-density lipoprotein cholesterol ratio (MHR) and variability of heart rate among patients with coronary heart disease (CHD). METHODS: 120 patients with CHD and 120 healthy individuals were respectively selected as the observation group and the control group. Allelic and genotypic differences of -429T>C, 1704G>T, 82G>S, MHR ratio and heart rate variability between the two groups and patients with different severity were analyzed. The correlation between their genotypes and MHR ratio and heart rate variability was analyzed. RESULTS: The 82G>S polymorphism of the RAGE gene and the allelic difference between the two groups and patients with different severity were statistically significant (P< 0.05). Compared with the control group and patients with mild to moderate phenotype, monocyte, total cholesterol, triglyceride, low density lipoprotein, MHR, low frequency in the observation group and patients with severe symptoms were significantly higher, while their high density lipoprotein, standard deviation of NN intervals (SDNN), standard deviation average of NN intervals (SDANN), root mean square successive differences, percentage of differences exceeding 50ms between adjacent normal number of intervals (PMN50), high frequency (HF) were significantly lower. The gene frequencies of G-Gly-T, T-Gly-T, G-Ser-T and G-Gly-C were correlated with SDNN, SDANN, rMSSD, PMN50, HF and MHR, but negatively correlated with low frequency. CONCLUSION: Polymorphisms of the RAGE gene in patients with coronary heart disease are associated with the MHR ratio and heart rate variability, which can be used as markers for the diagnosis and efficacy evaluation.

Paeonol suppresses the effect of ox-LDL on mice vascular endothelial cells by regulating miR-338-3p/TET2 axis in atherosclerosis.

Atherosclerosis is the common vascular disease. Vascular smooth muscle cell proliferation and vascular endothelial cell (VEC) dysfunction are involved in the causes of atherosclerosis. And oxidized low-density lipoprotein (ox-LDL)-induced vascular endothelial cells (VECs) are suitable models for studying atherosclerosis development. Paeonol was reported to repress ox-LDL-induced VEC progression. However, its detailed mechanism was not fully reported. MicroRNAs (miRNAs) acted as regulators in multiple diseases. Previous findings found that microRNA-338-3p (miR-338-3p) was overexpressed in Atherosclerosis process. However, the function and underlying mechanism of miR-338-3p in ox-LDL-treated VECs needed to be elucidated. The purpose of this research was to reveal the role of miR-338-3p in paeonol-regulated ox-LDL-induced VEC progression. Cell counting kit-8 (CCK-8) and flow cytometry were employed to determine cell viability and apoptosis, respectively. Moreover, the levels of IL-6 and IL-1ß were analyzed using enzyme-linked immunosorbent assay, as well as the contents of reactive oxygen species, lactate dehydrogenase, and malonic dialdehyde were investigated using related kits. Furthermore, quantitative real-time polymerase chain reaction was carried out to determine the expression of miR-338-3p. Western blot assay was conducted to detect the level of tet methylcytosine dioxygenase 2 (TET2). Besides, the interaction between miR-338-3p and TET2 was predicted by DIANA, and then confirmed by the dual-luciferase reporter assay and RNA immunoprecipitation assay. Ox-LDL repressed mice VEC viability, and promoted apoptosis, inflammatory response, and oxidative injury. Paeonol inhibited the effect of ox-LDL on the growth of the VECs. Furthermore, paeonol regulated VEC development via downregulating miR-338-3p expression. Interestingly, miR-338-3p targeted TET2 and inhibited TET2 expression. MiR-338-3p modulated ox-LDL-treated VEC growth through suppressing TET2 expression. We demonstrated that paeonol attenuated the effect of ox-LDL on the development of mice VECs via modulating miR-338-3p/TET2 axis, providing a theoretical basis for the treatment of AS.

LncRNA DYNLRB2-2 inhibits THP-1 macrophage foam cell formation by enhancing autophagy.

The aim of this study was to investigate whether long non-coding RNA (lncRNA) DYNLRB2-2 can inhibit foam cell formation by activating autophagy. The location of DYNLRB2-2 in THP-1-derived macrophages was analyzed by fluorescence in situ hybridization (FISH). Oxidized-low-density lipoprotein (ox-LDL) was used to induce the formation of foam cells, Oil Red O (ORO) staining and high-performance liquid chromatography (HPLC) were performed to detect accumulation of lipid droplets and the level of cholesterol concentration, respectively. The mRNA and protein level of ATP-binding cassette transporter A1 (ABCA1) were examined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting. Relative protein levels of (p-) liver kinase B1 (LKB1), (p-) AMP-activated protein kinase (AMPK), (p-) the mammalian target of rapamycin (mTOR) and autophagy markers (LC3 II, Beclin-1 and p62) in THP-1 macrophage-derived foam cells were analyzed by Western blotting. The levels of inflammatory factors [tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1ß] in THP-1 macrophage-derived foam cells were detected by enzyme-linked immunosorbent assay (ELISA). 3-MA and compound C were used to block autophagy. Our data show that DYNLRB2-2 inhibited the formation of THP-1 macrophage-derived foam cells and promotes cholesterol efflux (CE) by activating autophagy. DYNLRB2-2 caused autophagy by activating the signaling pathway of LKB1/AMPK/mTOR in foam cells. DYNLRB2-2 activated the LKB1/AMPK/mTOR signaling pathway via the miR-298/Sirtuin 3 (SIRT3) axis. Our data indicated that DYNLRB2-2 enhanced CE by regulating the LKB1/AMPK/mTOR autophagy signaling pathway through the miR-298/SIRT3 axis, thereby blocking the formation of foam cells from THP-1 macrophages.

Xanthoangelol Prevents Ox-LDL-Induced Endothelial Cell Injury by Activating Nrf2/ARE Signaling.

OBJECTIVE: Atherosclerosis (AS) contributes to the development of several cardiovascular diseases such as myocardial infarction and stroke. Oxidized low-density lipoprotein (Ox-LDL)-induced endothelial cell injury plays a key role in the pathogenesis of AS. Thus, this study was conducted to examine the effects of a naturally occurring flavonoid compound, xanthoangelol (XAG), on Ox-LDL-induced cell injury. MATERIALS AND METHODS: Human umbilical vein endothelial cells (HUVECs) were used as the in vitro cell model. The number of viable cells was determined using CCK-8 assay. Cell apoptosis was detected using Hoechst staining. Percentage of apoptotic cells was quantified by flow cytometry. The cellular levels of malondialdehyde (MDA), superoxide dismutase, catalase (CAT), and glutathione peroxidase were determined using enzyme-linked immunosorbent assays. The cellular reactive oxygen species level was detected by flow cytometry after fluorescence staining. The mRNA expression levels of nuclear factor-E2-related factor-2 (Nrf2), heme oxygenase-1 (HO-1), and NQO-1 were determined using quantitative real-time polymerase chain reaction assay. The protein levels of cleaved caspase-3, cleaved poly ADP-ribose polymerase, Bax, Bcl-2, Nrf2, Keap1, HO-1, and NQO-1 were measured by using Western blot assay. The HUVECs were transfected with Nrf2 siRNA to reduce the expression of Nrf2. RESULTS: XAG could effectively protect against Ox-LDL-stimulated cell death in HUVECs. These cytoprotective effects were due to its anti-apoptotic and anti-oxidant activities, as supported by the increase of SOD, CAT, and glutathione peroxidase activities, and the decrease of MDA and reactive oxygen species levels in injured HUVECs induced by Ox-LDL. Moreover, the results showed that XAG activated Nrf2/ARE signaling in a dose-dependent manner. Importantly, blockade of Nrf2 signaling using siRNA or specific inhibitor notably abolished the cytoprotective activities of XAG. CONCLUSIONS: These data suggest that XAG cytoprotects against Ox-LDL-induced cell injury through activating Nrf2/ARE-mediated antioxidative stress. Cumulatively, these findings show that EX has the potential to prevent and treat AS.

Curcumin Induces Ferroptosis in A549 CD133+ Cells through the GSH-GPX4 and FSP1-CoQ10-NAPH Pathways.

BACKGROUND: Cancer stem cells (CSCs) are characterized by an ability for unlimited proliferation and efficiency of self-renewal. The targeting of lung CSCs (LCSCs)-related signaling pathways represent a promising therapeutic strategy for treatment of lung cancer. Ferroptosis a potential strategy for LCSCs treatment, and curcumin cloud induce ferroptosis. In this study, we aimed to observe the effects of curcumin on LCSCs via ferroptosis-related pathways. METHODS: In this study, A549 cluster of differentiation (CD)133+ and A549 CD133- cells were isolated using magnetic bead-based separation. Colony formation and sphere formation assays, as well as cells injection in non-obese diabetes/severe combined immune deficiency (NOD/SCID) mice, were used to analyze the tumorigenic ability of cells differentially expressing CD133. A549 CD133+ cells were treated with different doses of curcumin (0, 10, 20, 40, 80 µM). Cell viability, glutathione peroxidase 4 (GPX4) and ferroptosis suppressor protein 1 (FSP1) expressions were measured. The 50% inhibitory concentration (IC50) of curcumin, two ferroptosis inducers, inhibitor of GPX4 (RSL3) and inhibitor of FSP1 (iFSP1), and a ferroptosis inhibitor, ferrostatin-1 (Fer-1), were used to investigate the mechanism underlying the effect of curcumin on ferroptosis in A549 CD133+ cells. RESULTS: A549 CD133+ cells had greater tumorigenic ability than A549 cells. Curcumin treatment suppressed the expressions of GPX4 (glutathione peroxidase 4) and FSP1 in A549 CD133+ cells, thereby inducing ferroptosis. RSL3 and iFSP1 respectively suppressed the GSH (glutathione)-GPX4 and FSP1 (ferroptosis suppressor protein 1)-CoQ10 (coenzyme Q10)-nicotinamide adenine dinucleotide (NADH) pathways in A549 CD133+ cells. However, the roles of curcumin were blocked by Fer-1 treatment. CONCLUSIONS: In this study, curcumin induced ferroptosis through inhibiting the GSH-GPX4 and FSP1-CoQ10-NADH pathways in A549 CD133+ cells, resulting in the inhibition of their self-renewal potential.

Biocatalyst and colorimetric biosensor of carcinoembryonic antigen constructed via chicken egg white-copper phosphate organic/inorganic hybrid nanoflowers.

In this article, the dual-functional chicken egg white-copper phosphate organic-inorganic hybrid nanoflowers (Cu-NFs), combining the functions of signal amplification and biological recognition, were prepared through a simple one-pot method. The Cu-NFs exhibit excellent biocatalytic activity of peroxidase and polyphenol oxidase. Besides, a biotin-labeled secondary antibody encapsulated Cu-NFs-2 (Cu-NFs-2@Biotin-NHS-Ab2) capture probe was prepared by using the interaction between avidin in the egg white and biotin. Based upon this superiority, the as-prepared Cu-NFs-2 were used in labeled avidin-biotin enzyme-linked immunosorbent assay (Cu-NFs-2 based-LAB-ELISA) to construct a sensitive colorimetric biosensor for the ultrasensitive detection of carcinoembryonic antigen (CEA). Under weak alkaline (pH = 7.5) conditions, the as-developed colorimetric sensor displayed a wide linear range of 0.05-40 ng/mL with a detection limit of 3.52 pg/mL. Furthermore, this colorimetric sensor has been successfully applied to the detection of CEA in human serum samples. Therefore, the as-developed colorimetric sensor has broad application prospects in the field of medical diagnosis and portable detection.

Contribution of IL-7/7R genetic polymorphisms in coronary heart disease in Chinese Han population.

BACKGROUND: Coronary heart disease (CHD) is a common chronic inflammatory disease. Interleukin (IL)-7/IL-7R has been reported to be involved in the development of CHD. However, the relationship between IL-7/7R genetic polymorphisms and CHD among the Han Chinese population remains unclear. METHODS: To examine whether IL-7/7R variants contributed to CHD, six single-nucleotide polymorphisms (SNPs) were genotyped by using the Agena MassARRAY platform in 499 CHD patients and 496 controls. Logistic regression was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs). The linkage disequilibrium was analyzed using Haploview software. The association between clinical parameters and IL-7/7R polymorphisms was determined by a one-way ANOVA. RESULTS: IL-7R rs969129 G (OR = 1.20, 95% CI: 1.00-1.43, p = 0.047) allele and GG (OR = 1.45, 95% CI: 1.01-2.08, p = 0.044) genotype carriers had a higher risk for CHD. IL-7R haplotype "ACAG" (OR = 1.43, 95% CI: 1.09-1.87, p = 0.010) conferred an increased CHD risk. Rs969129, rs6451231, and rs117173992 were related to CHD susceptibility in males and/or the subgroup of individuals aged >61 years. IL-7R rs969129, rs10053847, rs6451231, and rs118137916 variants were associated with diabetes in patients with CHD. Moreover, rs969129, rs6451231, and rs117173992 were associated with high-density lipoprotein cholesterol (HDL-C) concentrations, whereas rs118137916 and rs10053847 were associated with low-density lipoprotein cholesterol (LDL-C) levels (p < 0.05). CONCLUSION: IL-7/7R variants were related to the genetic predisposition of CHD in the Chinese Han population. These findings increase our knowledge regarding the effect of IL-7/7R on CHD.

Protective Effect of Ginkgolic Acid in Attenuating LDL Induced Inflammation Human Peripheral Blood Mononuclear Cells via Altering the NF-κB Signaling Pathway.

Oxidized low-density lipoprotein (ox-LDL) is considered as the significant maker of inflammatory reaction. ox-LDL was reported to play a crucial role in the pathogenesis of atherosclerosis (AS). In the current study, we scrutinize the suppressive effect of ginkgolic acid against ox-LDL induced an oxidative and inflammatory response in human microvascular endothelial cells (HMEC-1) and human peripheral blood mononuclear cells (nPBMCs) and explore the mechanism of action. HMEC-1 cells are treated with ox-LDL in the presence of different concentration of ginkgolic acid. MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was performed for the estimation of cell viability effect. Reactive oxygen species (ROS), inflammatory cytokines, and NF-κB activity are also estimated. For the hPBMCs assay, the cells were isolated from the healthy volunteers and cultured. The cells were further divided into different group and received the ginkgolic acid. Additionally, ROS, inflammatory marker such as prostaglandin E2 (PGE2), lipoxygenase (LOX), nitric oxide (NO), cyclooxygenase (COX) protein expression, and mRNA expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and vascular cell adhesion protein 1 (VCAM-1) were estimated in the ox-LDL treated group. The result exhibited that ginkgolic acid treatment induced the cell viability boosting in ox-LDL treatment and intracellular ROS significantly decreased by ginkgolic acid. Pro-inflammatory cytokines also downregulated via ginkgolic acid. Moreover, ginkgolic acid reduced the ox-LDL-induced NF-κB. The mRNA and protein expression of TNF-α, IL-6, and VCAM-1 considerably increased in the ox-LDL treated group and ginkgolic acid significantly reduced the mRNA and protein expression. An inflammatory marker such as PGE2, LOX, and NO were increased in the ox-LDL treated group and ginkgolic acid treated group exhibited the reduction of an inflammatory marker. Based on the result, we can conclude that ginkgolic acid significantly reduced and reversed the ox-LDL-induced modulation, suggesting its anti-inflammatory effect via the NF-κB pathway.

A double-Hertz model for adhesive contact between cylinders under inclined forces.

A generalized double-Hertz (D-H) model has been proposed to consider the adhesive contact between an elastic cylinder and an elastic half space under inclined forces. The normal traction is exactly the same as that in the conventional D-H model. The shear traction of finite value is distributed into a slipping zone and a non-slipping zone. In the slipping zone, the shear traction is proportional to the compressive pressure. With the model, adhesive contact behaviour between cylinders has been numerically illustrated. The shear-induced peeling has been demonstrated. The value of the ratio for shear traction to normal traction larger than friction coefficient has been found in part of the non-slipping zone. Those altogether are consistent with experiments.

[Effects of simvastatin on the left ventricular expression of transient outward potassium channel in rabbits with experimental heart failure].

OBJECTIVE: To investigate the effects of simvastatin on the left ventricular (LV) expression of transient outward potassium channel in rabbits with experimental heart failure (HF). METHODS: HF model was established by ligating the left anterior descending coronary artery of rabbits. Rabbits were randomized into simvastatin group (HF + S, 10 mg x kg(-1) x d(-1) for 10 weeks, n = 8), HF group (n = 9), and sham group (n = 9). Left ventricular remodeling and function were evaluated by echocardiography and hemodynamic measurements 10 weeks after operation. The mRNA and protein expressions of K(v)1.4, K(v)4.2 and K(v)4.3 potassium channel alpha subunit in LV were determined by semi-quantitative RT-PCR and Western blot. RESULTS: Simvastatin attenuated LV remodeling and improved cardiac function. The mRNA and protein expressions of K(v)1.4, K(v)4.2 and K(v)4.3 potassium channel alpha subunit in HF rabbits (0.48 +/- 0.09, 0.37 +/- 0.07, 0.42 +/- 0.11; 0.33 +/- 0.09, 0.22 +/- 0.07, 0.29 +/- 0.11) were significantly decreased compared with sham rabbits (0.85 +/- 0.08, 0.66 +/- 0.07, 0.67 +/- 0.08; 0.68 +/- 0.13, 0.53 +/- 0.15, 0.49 +/- 0.10, all P < 0.01), and these decreases could be attenuated by simvastatin (0.77 +/- 0.10, 0.50 +/- 0.10, 0.57 +/- 0.12; 0.58 +/- 0.10, 0.36 +/- 0.10, 0.43 +/- 0.12, all P < 0.01 vs. HF). CONCLUSION: Simvastatin not only attenuated LV remodeling and improved LV function but also prevented the downregulation of LV transient outward potassium channel expressions in rabbits with experimental HF.