Acrylamide induces neurotoxicity in zebrafish (Danio rerio) via NLRP3-mediated pyroptosis.

Acrylamide (ACR) is widely used in water treatment, cosmetics, dyes, paper manufacturing, and other industries. Evidence suggests that ACR exposure causes selective neurotoxicity in humans. The primary symptoms include extremity numbness, skeletal muscle weakness, and ataxia, skeletal muscle weakness. An experimental zebrafish (Danio rerio) embryo model was used in this study to assess the impact of ACR toxicity on the development of the zebrafish nervous system. The results showed that neurodevelopmental disorders, inflammatory reactions, and oxidative stress were common in zebrafish exposed to ACR. Furthermore, ACR exposure induces pyroptotic phenotypical nerve cells, pyroptosis-related protein activation, and inflammasome NLR family pyrin domain-containing 3 (NLRP3) expression. Caspy and Caspy2 expression was knocked down via CRISPR/Cas9 to further investigate the pyroptotic mechanism, showing that these two targets alleviated the inflammatory reaction and neurodevelopmental disorder caused by ACR. Moreover, the Caspy-mediated classic pathway may be vital for the pyroptosis caused by ACR. In conclusion, this study is the first to show that ACR can activate NLRP3 inflammation to cause neurotoxicity in zebrafish via the Caspy pathways, which differs from the traditional exogenous infection model.

Acrylamide induces intrinsic apoptosis and inhibits protective autophagy via the ROS mediated mitochondrial dysfunction pathway in U87-MG cells.

Acrylamide (ACR) is a potential neurotoxin commonly found in the environment, as well as in food repeatedly exposed heat processing, but the mechanism underpinning ACR-induced neurotoxicity remains unclear. This study investigated the potential association and underlying signal transduction of oxidative stress, apoptosis, and autophagy associated with ACR-triggered neurotoxicity. Therefore, U87-MG cells were treated with varying ACR concentrations, while the cell activity reduction depended on the specific dosage and time parameters. Biochemical analyses showed that ACR significantly increased the reactive oxygen species (ROS), malondialdehyde (MDA), and Ca2+ levels while decreasing the glutathione (GSH) levels and mitochondrial membrane potential (ΔΨm), finally leading to a higher cell apoptotic rate. Moreover, ACR induced U87-MG cell apoptosis and autophagy via ROS-triggered expression in the mitochondrial apoptosis pathway, NF-κB activation, and autophagosome accumulation. In addition, the autophagosome accumulation induced by ACR could probably be ascribed to blocked autophagic flux, inhibiting the autophagosomes from combining with lysosomes, while the inhibition of autophagy caused by ACR further promoted the initiation of apoptosis. In conclusion, the results indicated that the apoptotic and autophagic pathways responded to ACR-induced neurotoxicity. However, inhibited protective autophagy further promoted apoptotic progression. New insights may be derived from these cellular responses that can help develop diverse pathway strategies for assessing the risk posed by ACR.HIGHLIGHTSACR induced mitochondrial- and caspase-dependent apoptosis in U87-MG cells.ACR regulated the autophagic markers and blocked autophagic flux in U87-MG cells.ACR inhibited protective autophagy and promoted apoptotic initiation in U87-MG cells.

Chitopentaose inhibits hepatocellular carcinoma by inducing mitochondrial mediated apoptosis and suppressing protective autophagy.

Hepatocellular carcinoma (HCC) is one of the most prevalent and deadliest cancers. In this study, the anti-tumor effect of singular degree of polymerization (DP) chitooligosaccharides (COS) (DP 2-5) and the underlay molecular mechanisms were investigated on HCC cell line HepG2. MTT assay showed that (GlcN)5 have the best anti-proliferation effect among the different DP of COS (DP2-5). Furthermore, the administration of (GlcN)5 could decrease mitochondrial membrane potential, release cytochrome c into cytoplasm, activate the cleavage of Caspases9/3, thus inducing mitochondrial-mediated apoptosis in HepG2 cells (accounting for 24.57 ± 2.25%). In addition, (GlcN)5 treatment could increase the accumulation of autophagosomes. Further investigation showed that (GlcN)5 suppressed protective autophagy at the fusion of autophagosomes and lysosomes. Moreover, the inhibition of protective autophagy flux by (GlcN)5 could further decrease cell viability and increase the apoptosis rate. Our findings suggested that (GlcN)5 suppressed HepG2 proliferation through inducing apoptosis via the intrinsic pathway and impairing cell-protective autophagy. COS might have the potential to be an agent for lowering the risk of HCC.

Efficient inhibition of Cronobacter biofilms by chitooligosaccharides of specific molecular weight.

Biofilms enable Cronobacter spp. to contaminate food, infect infants and resist different environmental stresses, especially desiccation, which is the main reason why Cronobacter can survive in powdered infant formula (PIF) for a long time. Considering the high lethality of Cronobacter infection in infants, it is important to find efficient and safe inhibitors of Cronobacter biofilms. In this study, we found that chitooligosaccharides (COS) with a molecular weight of 2000 Da efficiently inhibited Cronobacter biofilms, especially in skim milk broth. The minimum biofilm inhibitory concentration (MBIC77) of COS was as low as 20 µg/mL, which is lower than that reported in most previous studies. Besides, the elimination rate of COS for Cronobacter mature biofilms was 50% when the concentration was 10 mg/mL. COS could significantly inhibit soluble polysaccharide secretion and biofilm cell growth, as well as change the cell membrane permeability of Cronobacter. These might be the possible reasons for COS's efficient inhibition of Cronobacter biofilms. However, during the inhibition, five important genes-related to biofilm formation-flhD, flgJ, luxR, ompA, and wcaJ-were all up-regulated after COS treatment, except the gene bcsA. In summary, our findings showed that COS could be used as an efficient and safe inhibitor against Cronobacter biofilms for better control of Cronobacter contamination and infection.

Kinetics and equilibria of the chromatographic separation of maltose and trehalose.

Trehalose, a nonreducing disaccharide, has been extensively applied to food, cosmetics, and pharmaceutical goods. The resultant solution of trehalose prepared by enzymatic methods includes high amounts of maltose. However, it is quite difficult to separate maltose and trehalose on an industrial scale because of their similar properties. In this paper, a high-performance resin was selected as a stationary phase to separate trehalose and maltose, and the resolution of these sugars was 0.59. The potential of a cation exchange resin was investigated as the stationary phase in separating trehalose and maltose using deionized water as the mobile phase. Based on the equilibrium dispersive model, the axial dispersion coefficients and overall mass transfer coefficients of maltose and trehalose were determined by moment analysis at two different temperatures, 50 and 70°C. Other parameters, including the column void and the adsorption isotherms, were also determined and applied to simulate the elution curves of trehalose and maltose. The simulated results matched the experimental data, validating the parameters. The optimized parameters are critical to the chromatographic separation of trehalose and maltose on an industrial scale.

[In vitro suspension and bioreactor culture of hematopoietic cells].

Stirred culture offers a number of advantages over static systems as it maintains a stable, homogeneous culture environment and is easy to scale-up. This paper focused on the development and application of stirred tank bioreactor to culture hematopoietic cells. Preliminary study of stirred culture of hematopoietic cells was carried out in cord blood mononuclear cells culture in spinner flask. The results showed that the amplification rates of total cell, CFU-GM and BFU-E, with the exception of CFU-Mk, were greater in spinner flask than T-flask. The number of total cells increased 20 fold after 14 days incubation in spinner flask. The amplification rates of CFU-GM, CFU-Mk and BFU-E reached maximum at 10th day, 10th day and 7th day respectively, and the maximal amplification rates were 9.2-fold, 5.5-fold and 2.4-fold respectively, whereas the rate of CD34+ cells in spinner flask was (6.7 +/- 4.0)-fold at day 10. These results indicated that the stirred culture system is better than the static culture systems for hematopoietic cell proliferation. The biocompatibility of cord blood MNC to different types of materials used in bioreactors was also tested. The results showed that glass, stainless steel 316L and polytetraflouroethylene (PTFE) supported the growth of hematopoietic cells well. A higher cell density was reached in stirred bioreactors with controlled pH and DO than static culture. These findings suggested that the controlled large-scale culture could be used to overcome the clinical shortage of hematopoietic cells.