Activation of α7 nicotinic acetylcholine receptor protects against oxidant stress damage through reducing vascular peroxidase-1 in a JNK signaling-dependent manner in endothelial cells.

AIM: Alpha7 nicotinic acetylcholine receptor (α7nAChR), a subtype of nAChR regulating neurotransmission in central nervous system, is an essential regulator of cholinergic anti-inflammatory pathway in periphery. The present study was to determine the effects of activation of α7nAChR on oxidant stress-induced injury in endothelial cells. METHODS: Cultured human umbilical vein endothelial cells were treated with H2O2 (400 µM) or H2O2 plus PNU-282987 (10 µM). Cell viability and membrane integrity were measured. Annexin V + PI assay, immunoblotting of bcl-2, bax and cleaved capase-3, and immunofluorescence of apoptosis inducing factor (AIF) were performed to evaluate apoptosis. Protein expression of vascular peroxidase-1 (VPO-1) and phosphor-JNK were measured by immunoblotting. RESULTS: Activation of α7nAChR by a selective agonist PNU-282987 prevented H2O2-indced decrease of cell viability and increase of lactate dehydrogenase release. Activation of α7nAChR markedly reduced cell apoptosis and intracellular oxidative stress level. Moreover, activation of α7nAChR reduced H2O2-induced VPO-1 protein upregulation and JNK1/2 phosphorylation. The inhibitory effect of α7nAChR activation on VPO-1 was blocked by JNK inhibitor SP600125. In addition, pretreatment of α7nAChR antagonist methyllycaconitine blocked the cytoprotective effect of PNU-282987. CONCLUSION: These results provide the first evidence that activation of α7nAChR protects against oxidant stress-induced damage by suppressing VPO-1 in a JNK signaling pathway-dependent manner in endothelial cells.

Correction: Tumor Immunotherapy-Related Information on Internet-Based Videos Commonly Used by the Chinese Population: Content Quality Analysis.

[This corrects the article DOI: 10.2196/50561.].

Tumor Immunotherapy-Related Information on Internet-Based Videos Commonly Used by the Chinese Population: Content Quality Analysis.

BACKGROUND: Tumor immunotherapy is an innovative treatment today, but there are limited data on the quality of immunotherapy information on social networks. Dissemination of misinformation through the internet is a major social issue. OBJECTIVE: Our objective was to characterize the quality of information and presence of misinformation about tumor immunotherapy on internet-based videos commonly used by the Chinese population. METHODS: Using the keyword "tumor immunotherapy" in Chinese, we searched TikTok, Tencent, iQIYI, and BiliBili on March 5, 2022. We reviewed the 118 screened videos using the Patient Education Materials Assessment Tool-a validated instrument to collect consumer health information. DISCERN quality criteria and the JAMA (Journal of the American Medical Association) Benchmark Criteria were used for assessing the quality and reliability of the health information. The videos' content was also evaluated. RESULTS: The 118 videos about tumor immunotherapy were mostly uploaded by channels dedicated to lectures, health-related animations, and interviews; their median length was 5 minutes, and 79% of them were published in and after 2018. The median understandability and actionability of the videos were 71% and 71%, respectively. However, the quality of information was moderate to poor on the validated DISCERN and JAMA assessments. Only 12 videos contained misinformation (score of >1 out of 5). Videos with a doctor (lectures and interviews) not only were significantly less likely to contain misinformation but also had better quality and a greater forwarding number. Moreover, the results showed that more than half of the videos contain little or no content on the risk factors and management of tumor immunotherapy. Overall, over half of the videos had some or more information on the definition, symptoms, evaluation, and outcomes of tumor immunotherapy. CONCLUSIONS: Although the quality of immunotherapy information on internet-based videos commonly used by Chinese people is moderate, these videos have less misinformation and better content. Caution must be exercised when using these videos as a source of tumor immunotherapy-related information.

Pharmacokinetics of colistin in cerebrospinal fluid after intraventricular administration alone in intracranial infections.

The aim of this study was to investigate the pharmacokinetics of colistin in cerebrospinal fluid (CSF) after intraventricular (IVT) administration of colistin methanesulfonate (CMS) for central nervous system (CNS) infections caused by multidrug-resistant Gram-negative bacteria. Ten patients with CNS infection were treated with CMS (active substance colistin equivalent to 100 000 units, every 24 h) by IVT administration. After 3 days of treatment, the concentration of colistin in the CSF was determined by selective ultra-performance liquid chromatography (UPLC) at 2, 4, 6, 8, 12 and 24 h after CMS administration. A pharmacokinetic analysis was performed using Phoenix WinNonlin. Following IVT administration of CMS, the estimated colistin apparent CSF half-life (t1/2) was 10.46 ± 6.98 h, the average peak colistin concentration (Cmax) was 16.95 ± 7.39 µg/mL and the average time to peak concentration (Tmax) was 4.6 ± 0.97 h. The measured trough concentration (Cmin; colistin concentration in CSF at 24 h after administration of CMS) was 1.12-8.33 µg/mL and the average Cmin was 2.91 ± 2.11 µg/mL. CSF concentrations of colistin were above the minimum inhibitory concentration (MIC) of 0.5 µg/mL at 24 h after IVT administration in all patients. Microbiological cure was observed in all patients. In conclusion, this is the first study of colistin pharmacokinetics in CSF after IVT administration alone in patients with CNS infection. It provides essential data for designing relatively safe and effective CMS dosing regimens.

Anchoring of ulex europaeus agglutinin to chitosan nanoparticles-in-microparticles and their in vitro binding activity to bovine submaxillary gland mucin.

Focused on the natural biodegradable material of chitosan (CS), this investigation concerned its spray-dried nanoparticles-in-microparticles (NiMPs) modified with ulex europaeus agglutinin (UEA). Chitosan nanoparticles were obtained by ionotropic gelation process with pentasodium tripolyphosphate as gelatinizer. Then UEA lectin was bound onto the CS nanoparticles activated by glutaraldehyde. The conjugated spherical UEA-CS-NiMPs, prepared by spray drying method, exhibited 12-85% coupling efficiency of UEA depending upon the amount of activator glutaraldehyde. And the UEA-grafted particles showed additional higher binding tendency with bovine submaxillary gland mucin as compared to the plain chitosan microparticles. Furthermore, the activity and intrinsic fucose-specificity of UEA were still maintained after the covalent modification. It is thus evident that the UEA anchored CS-NiMPs might be used as a potential drug delivery system targeted to the specific regions of gastrointestinal tract.

Preparation and characterization of sodium ferulate entrapped bovine serum albumin nanoparticles for liver targeting.

Sodium ferulate (SF) loaded nanoparticles were prepared by desolvation procedure and subsequent cross-linking of the wall material of bovine serum albumin (BSA). Several factors in the nanoencapsulation process, such as the addition rate of the desolvation agent, composition of BSA and SF solution, amount of the cross-linker glutaraldehyde, were investigated to elucidate their influences on the particle size, zeta potential, drug loading and encapsulation efficiency of the resulted nanoparticles. The obtained spherical nanoparticles were negative charged with zeta potential from -20 to -40 mV, and characterized between 100 and 200 nm with a narrow size distribution. In the condition of introducing 1.0 mL 8% glutareldehyde per mg of BSA, the drug entrapment efficiency (EE) of 80% (w/w) and loading capacity of about 16% (w/w) could be achieved for the cross-linked BSA nanoparticles with SF encapsulated (SF-BSA-NP). And the drug EE was decreased along with the increasing amount of glutareldehyde used for cross-linking. The in vitro drug release properties of SF-BSA-NP behaved with an initial burst effect and then sustained-release stage. To some extent, the drug release rate could be adjusted by cross-linking with different amount of glutaraldehyde. Compared with SF solution, SF-BSA-NP showed a much higher drug distribution into liver and a lower drug concentration in other tissues, after intravenously injected to mice. So, BSA based nanoparticles might be a suitable controlled released carrier for the freely water-soluble drug SF and further hepatic targeted drug delivery.

Nicotinic acetylcholine receptor α7 subunit improves energy homeostasis and inhibits inflammation in nonalcoholic fatty liver disease.

OBJECTIVE: Nonalcoholic fatty liver disease (NAFLD) is one of the most common liver diseases worldwide; yet, the pathogenesis of the disorder is not completely understood. The nicotinic acetylcholine receptor α7 subunit (α7nAChR) plays an indispensable role in the vagus nerve-regulated cholinergic anti-inflammatory pathway. METHODS: In the present study, we investigated the key role of α7nAChR in NAFLD development. Male wild-type (WT) and α7nAChR knockout (α7nAChR-/-) mice were fed a normal chow or a high-fat diet (HFD) for 16weeks to induce NAFLD. RESULTS: We found that both the mRNA and protein levels of α7nAChR in the liver tissue of NAFLD mice were significantly higher than those in mice fed normal chow. There were no differences in food intake, body weight, hepatic cholesterol and triglyceride contents, and insulin sensitivity between WT and α7nAChR-/- mice under normal condition. When the WT and α7nAChR-/- mice were challenged with HFD, the body weight of α7nAChR-/- mice became higher than that of WT mice. The oxygen consumption and energy expenditure in HFD-fed α7nAChR-/- mice were significantly lower than that in HFD-fed WT mice. The HFD-fed α7nAChR-/- mice also showed more aggravated hepatic lipid accumulation, steatosis and oxidative stress than HFD-fed WT mice. Macrophage infiltration; mRNA levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-1ß; and liver fibrosis were significantly accelerated in HFD-fed α7nAChR-/- mice compared to that in HFD-fed WT mice. In addition, the bolus insulin injection-activated insulin signaling pathway, which was reflected by the phosphorylation of insulin receptor at Tyr1162/Tyr1163 site (p-IRTyr1162/Tyr1163), insulin receptor substrate-1 at Tyr612 site (p-IRS-1Tyr612) and Akt at Ser473 (p-AktSer473), was significantly compromised in liver tissues of HFD-fed α7nAChR-/- mice relative to HFD-fed WT mice. Finally, pharmacologically activation of α7nAChR in HFD-fed mice, with a selective agonist PNU-282987, remarkably ameliorated the hepatic steatosis, inflammatory cell infiltration and fibrosis. CONCLUSION: In conclusion, our results demonstrate that activation of α7nAChR improves energy homeostasis and inhibits inflammation in nonalcoholic fatty liver disease.

[Oral vaccination and vaccine-entrapped microparticle delivery system].

In order to elucidate the physiological basis for mucosal immunity of oral vaccination and to present the essential carrier of microparticles or nanoparticles used to investigate the orally delivered vaccine, the features of antigen presentation and mucosal immunereaction in gut-associated lymphoid tissues were analyzed. Considered the morphological and physiological barriers of the gastrointestinal tract, absorption and transport of particulates were further discussed. And the studies about particulate dosage forms for oral vaccine delivery were also summarized in this review. Peyer s patches and M-cells, involved in immunoregulation, are significant areas performing the critical role in oral vaccine. The applied vesicle of microparticles could overcome the barriers of gastrointestinal tract. Oral vaccination was endued with new connotation, especially the enhanced transport and immunization efficiencies promoted by the lectin anchored particles. In conclusion, oral vaccination mediated by particulate carrier via mucosal immune system, would contribute to the site-specific triggering and signal magnification. For vaccines, the prospects for the application of these promising carrier systems might have potential attraction for scientific research and commercial development.