Shear stress leads to the dysfunction of endothelial cells through the Cav-1-mediated KLF2/eNOS/ERK signaling pathway under physiological conditions.

To investigate the mechanism of shear stress on endothelial cell dysfunction for providing a theoretical basis for the reduction of arteriovenous fistula dysfunction. The in vitro parallel plate flow chamber was used to form different forces and shear stress to mimic the hemodynamic changes in human umbilical vein endothelial cells, and the expression and distribution of krüppel-like factor 2 (KLF2), caveolin-1 (Cav-1), p-extracellular regulated protein kinase (p-ERK), and endothelial nitric oxide synthase (eNOS) were detected by immunofluorescence and real-time quantitative polymerase chain reaction. With the prolongation of the shear stress action time, the expression of KLF2 and eNOS increased gradually, while the expression of Cav-1 and p-ERK decreased gradually. In addition, after cells were exposed to oscillatory shear stress (OSS) and low shear stress, the expression of KLF2, Cav-1, and eNOS decreased and the expression of p-ERK increased. The expression of KLF2 increased gradually with the prolongation of action time, but it was still obviously lower than that of high shear stress. Following the block of Cav-1 expression by methyl ß-cyclodextrin, eNOS expression decreased, and KLF2 and p-ERK expression increased. OSS may lead to endothelial cell dysfunction by Cav-1-mediated KLF2/eNOS/ERK signaling pathway.

[Correlation analysis of clinical indicators and liver failure-related prognostic score associated with prognosis in patients with amanita phalloides poisoning].

OBJECTIVE: To analyze and compare the clinical indicators and the liver failure-related prognostic score of patients with amanita phalloides poisoning with different prognoses, and to explore potential prognostic indicators. METHODS: A retrospective case-control study was conducted. The clinical data of 52 patients with amanita phalloides poisoning admitted to the department of emergency of Xijing Hospital Affiliated to Air Force Medical University from September 2016 to September 2021 were collected, including general information (gender, age), clinical indicators at admission [mean arterial pressure (MAP), total bilirubin (TBil), aspartate transaminase (AST), alanine transaminase (ALT), albumin (ALB), serum creatinine (SCr), blood urea nitrogen (BUN), creatine kinase (CK), D-dimer, fibrinogen degradation product (FDP), prothrombin time (PT), activated partial thromboplastin time (APTT), prothrombin activity (PTA), international normalized ratio (INR), white blood cell count (WBC), platelet count (PLT)], liver failure-related prognostic score [sequential organ failure assessment (SOFA), chronic liver failure (CLIF)-SOFA score, European Foundation for the Study of Chronic Liver Failure-organ failure (CLIF-C OF)], and 28-day outcome. The clinical indicators and liver failure-related prognostic scores of the patients with different prognoses were compared. Receiver operator characteristic curve (ROC curve) was used to determine the prognostic value of statistically significant indicators between different prognosis of patients with amanita poisoning. RESULTS: A total of 45 patients were enrolled, of which 38 survived and 7 died within 28 days. The coagulation indicators including PT, APTT, INR, and liver failure-related prognostic scores including SOFA score, CLIF-SOFA score, and CLIF-C OF score in the patients of death group were significantly higher than those in the survival group [PT (s): 69.59±15.94 vs. 25.99±4.64, APTT (s): 83.44±17.82 vs. 42.64±3.79, INR: 6.13±1.47 vs. 2.07±0.33, SOFA score: 11.57±1.38 vs. 6.03±0.77, CLIF-SOFA score: 9.86±2.17 vs. 5.55±0.67, CLIF-C OF score: 11.71±0.97 vs. 8.37±0.35], and PLT was significantly lowered (×109/L: 80.57±29.65 vs. 169.60±11.80, all P < 0.05). ROC curves showed that coagulation indicators including PT, APTT, INR, PLT, and liver failure-related prognostic scores including SOFA score and CLIF-C OF score were associated with the prognosis of patients with amanita phalloides poisoning, with the area under the ROC curve (AUC) of > 0.75. The sensitivity of the clinical indicators was above 85%, and the AUC and specificity of INR were the highest, which were 0.88 [95% confidence interval (95%CI) was 0.74-1.00] and 83.0%, respectively; meanwhile, the sensitivity of the liver failure-related prognostic scores was 100%, and the AUC and specificity of the CLIF-C OF score were the highest, which were 0.86 (95%CI was 0.74-0.99) and 66.0%, respectively. CONCLUSIONS: INR and CLIF-C OF score can be used to evaluate the poor prognosis of patients with amanita phalloides poisoning.

Strategies for Preparing Different Types of Lipid Polymer Hybrid Nanoparticles in Targeted Tumor Therapy.

At present, cancer is one of the most common diseases in the world, causing a large number of deaths and seriously affecting people's health. The traditional treatment of cancer is mainly surgery, radiotherapy or chemotherapy. Conventional chemotherapy is still an important treatment, but it has some shortcomings, such as poor cell selectivity, serious side effects, drug resistance and so on. Nanoparticle administration can improve drug stability, reduce toxicity, prolong drug release time, prolong system half-life, and bring broad prospects for tumor therapy. Lipid polymer hybrid nanoparticles (LPNs), which combine the advantages of polymer core and phospholipid shell to form a single platform, have become multi-functional drug delivery platforms. This review introduces the basic characteristics, structure and preparation methods of LPNs, and discusses targeting strategies of LPNs in tumor therapy in order to overcome the defects of traditional drug therapy.

Effects of immune cells and cytokines on inflammation and immunosuppression in the tumor microenvironment.

Chronic inflammation and immune responses are two core element that characterize the tumor microenvironment. A large number of immune/inflammatory cells (including tumor associated macrophages, neutrophils and myeloid derived suppressor cells) as well as cytokines (such as IL-6, IL-10, TGF-ß) are present in the tumor microenvironment, which results in both a chronic inflammatory state and immunosuppression. As a consequence tumor cell migration, invasion, metastasis and anticancer drug sensitivity are modulated. On the one hand, secreted cytokines change the function of cytotoxic T lymphocytes and antigen presenting cells, thereby inhibiting tumor specific immune responses and consequently inducing a special immunosuppressive microenvironment for tumor cells. On the other hand, tumor cells change the differentiation and function of immune/inflammatory cells in the tumor microenvironment especially via the NF-κB and STAT3 signaling pathways. This may promote proliferation of tumor cells. Here we review these double edged effects of immune/inflammatory cells and cytokines on tumor cells, and explored their interactions with inflammation, hypoxia, and immune responses in the tumor microenvironment. The tumor inflammatory or immunosuppressive reactions mediated by the high activity of NF-κB or STAT3 can occur alone or simultaneously, and there is a certain connection between them. Inhibiting the NF-κB or STAT3 signaling pathway is likely to curb the growth of tumor cells, reduce the secretion of pro-inflammatory factors, and enhance the anti-tumor immune response.

Design and development of spirulina polysaccharide-loaded nanoemulsions with improved the antitumor effects of paclitaxel.

Aims: In this study, we prepared spirulina polysaccharides into spirulina polysaccharide-loaded nanoemulsions (SPS-NEs), and determined the antitumor effect of SPS-NEs, when combined with paclitaxel (PTX).Methods: SPS-NEs were prepared by a phase transformation method. The Characterisation and stability of SPS-NEs was measured. The antitumor effect of SPS-NEs combined with PTX was determined by S180 cells or RAW 264.7 macrophages and S180 tumour-bearing mice.Results: SPS-NEs were spherical and stable, the particle size of SPS-NEs was 84.6 ± 3.31 nm, PDI = 0.235 ± 0.02. PTX + SPS-NEs exhibited a much greater toxicity against RAW 264.7 cells than PTX. PTX + SPS-NEs increased the release of NO, IL-6 and TNF-α, and the expression of p-p65 NF-κB, p-I-κB, TLR4. In addition, PTX + SPS-NEs significantly inhibited tumour growth by 72.82% and increased the secretion of serum IL-2, TNF-α and IFN-γ.Conclusions: SPS-NEs can regulate immunity through TLR4/NF-κB signalling pathways, which enhances the anti-tumour effect of PTX.

Psoralen-loaded lipid-polymer hybrid nanoparticles enhance doxorubicin efficacy in multidrug-resistant HepG2 cells.

BACKGROUND: Psoralen (PSO), a major active component of Psoralea corylifolia, has been shown to overcome multidrug resistance in cancer. A drug carrier comprising a lipid-monolayer shell and a biodegradable polymer core for sustained delivery and improved efficacy of drug have exhibited great potential in efficient treatment of cancers. METHODS: The PSO-loaded lipid polymer hybrid nanoparticles were prepared and characterized. In vitro cytotoxicity assay, cellular uptake, cell cycle analysis, detection of ROS level and mitochondrial membrane potential (ΔΨm) and western blot were performed. RESULTS: The P-LPNs enhanced the cytotoxicity of doxorubicin (DOX) 17-fold compared to free DOX in multidrug resistant HepG2/ADR cells. Moreover, P-LPNs displayed pro-apoptotic activity, increased levels of ROS and depolarization of ΔΨm. In addition, there were no signifi-cant effects on cellular uptake of DOX, cell cycle arrest, or the expression of P-glycoprotein. Mechanistic studies suggested that P-LPNs enhanced DOX cytotoxicity by increased release of cytochrome c and enhanced caspase3 cleavage, causing apoptosis in HepG2/ADR cells. CONCLUSION: The lipid-polymer hybrid nanoparticles can be considered a powerful and promising drug delivery system for effective cancer chemotherapy.

Preparation and evaluation of spirulina polysaccharide nanoemulsions.

The aim of the present study was to prepare spirulina polysaccharide (PSP) into an oral nanoemulsion (NE) with the aim of improving its oral bioavailability and prolonging its sustained release effect. The PSP­NE was prepared through a phase transformation method, and its formulation components were screened through the use of a pseudo­ternary phase diagram. The optimal formulation of PSP­NE was determined to be: 11.9% Span 80, 6.0% Tween-80, 9.0% ethanol, 62.8% soybean oil, and 10.3% PSP aqueous solution. The prepared PSP­NE was clear and transparent, had a uniform color and spherical morphology, exhibited stability and no adhesion. The average particle size was 79.93±19 nm, the polydispersity index was 0.185±0.04 (n=3), and the entrapment rate was 62%. Small­animal imaging results showed that the prepared PSP­NE exhibited a sustained release and tissue effect in contrast to the PSP aqueous solution. The present study showed that the prepared PSP­NE not only exhibited a sustained release and tissue effect in contrast to the PSP aqueous solution, but also had superior performance in terms of antitumor and antioxidant effects.

Extraction of Polysaccharide from Spirulina and Evaluation of Its Activities.

BACKGROUND: Polysaccharide of Spirulina platensis (PSP) is a kind of water-soluble polysaccharide extracted from Spirulina platensis. It has been proved to have antitumor, antioxidation, antiaging, and antivirus properties. And it has a promising prospect for wide application. OBJECTIVE: This study aims to identify an extraction process for high-purity polysaccharide in Spirulina (PSP) through a series of optimization methods and then evaluates its initial antiaging activities. METHODS: Four kinds of extraction methods-hot-water extraction, alkali extraction, ultrasonic-assisted extraction, and freeze-thaw extraction-were compared to find the optimal one, which was further optimized by response surface methodology. PSP was obtained after the crude PSP was deproteinized and depigmented. The antiaging effects of PSP were preliminarily evaluated through in vitro cell experiments. RESULTS: The alkali extraction method was determined as the optimal method, with the optimized extraction process consisting of a solid-liquid ratio of 1 : 50, a pH value of 10.25, a temperature of 89.24°C, and a time of 9.99 h. The final PSP contained 71.65% of polysaccharide and 8.54% of protein. At a concentration of 50 µg/mL, PSP exerted a significant promoting effect on the proliferation and traumatic fusion of human immortalized epidermal cells HaCaT. CONCLUSION: An extraction method for high-purity PSP with a high extraction rate was established, and in vitro results suggest antioxidation and antiaging activities.

Preparation of psoralen polymer-lipid hybrid nanoparticles and their reversal of multidrug resistance in MCF-7/ADR cells.

Multidrug resistance (MDR) is the leading cause of failure for breast cancer in the clinic. Thus far, polymer-lipid hybrid nanoparticles (PLN) loaded chemotherapeutic agents has been used to overcome MDR in breast cancer. In this study, we prepared psoralen polymer-lipid hybrid nanoparticles (PSO-PLN) to reverse drug resistant MCF-7/ADR cells in vitro and in vivo. PSO-PLN was prepared by the emulsification evaporation-low temperature solidification method. The formulation, water solubility and bioavailability, particle size, zeta potential and entrapment efficiency, and in vitro release experiments were optimized in order to improve the activity of PSO to reverse MDR. Optimal formulation: soybean phospholipids 50 mg, poly(lactic-co-glycolic) acid (PLGA) 15 mg, PSO 3 mg, and Tween-80 1%. The PSO-PLN possessed a round appearance, uniform size, exhibited no adhesion. The average particle size was 93.59 ± 2.87 nm, the dispersion co-efficient was 0.249 ± 0.06, the zeta potential was 25.47 ± 2.84 mV. In vitro analyses revealed that PSO resistance index was 3.2, and PSO-PLN resistance index was 5.6, indicating that PSO-PLN versus MCF-7/ADR reversal effect was significant. Moreover, PSO-PLN is somewhat targeted to the liver, and has an antitumor effect in the xenograft model of drug-resistant MCF-7/ADR cells. In conclusion, PSO-PLN not only reverses MDR but also improves therapeutic efficiency by enhancing sustained release of PSO.

Identification of Vibrio cholerae serotypes in high-risk marine products with non-gel sieving capillary electrophoresis.

Vibrio cholerae, a natural inhabitant of the marine environment, poses a threat to human health, and its new epidemic variants have been reported. A method of multiplex polymerase chain reaction-capillary electrophoresis-laser-induced fluorescence (PCR-CE-LIF) detection has been developed to detect and identify V. cholerae in marine products sensitively, rapidly, and reliably. Four sets of primers were selected to amplify genus-specific VCC gene, O139 serogroup-specific O139 gene, O1 serogroup-specific O1 gene, and ctxA gene associated with the CT toxin of enterotoxigenic V. cholerae. The PCR products were detected using CE-LIF with SYBR Gold serving as the DNA fluorescent dye. The parameters of PCR and the separation conditions of CE-LIF were optimized. Under the optimal conditions, V. cholerae was detected and four serotypes were identified simultaneously within 8 min. The alignment analysis showed that the PCR products had good agreement with the published sequences from GenBank, indicating that the primers selected in this study had high specificity and the PCR results were reliable. The proposed method could detect 5 to 20 cfu/ml V. cholerae. The intraday precisions of migration time and peak area of DNA marker and PCR products were in the ranges of 1.60-2.56% and 1.60-6.29%, respectively. The specificity results showed that only five standard bacteria used in this study showed the specific peaks when the target bacteria were mixed with seven other common intestinal pathogenic bacteria at the same concentration. The assay was applied to 71 high-risk marine products, and different serotypes of V. cholerae could be identified sensitively and reliably.