CO2 responsive self-standing Pickering emulsion gel stabilized with rosin-based surfactant modified cellulose nanofibrils.

Emulsion gel was developed to provide desirable texture, palatability and functionality to food products. Tunable stability of emulsions is often desired, as in certain situations, the chemical content release usually relies on emulsion induced destabilization of the droplet. However, the destabilization for emulsion gel is difficult because of the formation of highly entangled networks. To address this issue, a fully biobased Pickering emulsion gel stabilized by cellulose nanofibrils (CNF) modified with a CO2 responsive rosin-based surfactant, maleopimaric acid glycidyl methacrylate ester 3-dimethylaminopropylamine imide (MPAGN) was reported. The emulsification/de-emulsification can be reversibly regulated because this surfactant has sensitive CO2 responsive property. MPAGN can be reversibly between active cationic (MPAGNH+) and inactive nonionic (MPAGN) responsive to CO2 and N2. The microstructure of the emulsion gel was observed and compared before and after the response. The rheological properties of emulsion gel stabilized by different concentrations of MPAGNH+ and different contents of CNF were studied separately. As 0.2 wt% CNF was dispersed in 1 mM MPAGNH+ solution, the obtained emulsion can be self-standing for long duration. The rheology study indicated that these emulsions show typical gel characteristics with shear-thinning behavior. The stabilization mechanism of these gel emulsion is a synergistic effect caused by the combination of CO2 responsive Pickering emulsion and intertwined network caused by the hydrogen-bond interaction among CNF.

Lactate-driven macrophage polarization in the inflammatory microenvironment alleviates intestinal inflammation.

Background: Lactate has long been considered an intermediate by-product of glucose metabolism. However, in recent years, accumulating evidence reveals that lactate has unique biological activities. In previous studies, lactate signaling was shown to inhibit inflammation. Furthermore, in vitro experiments have shown that lactate can promote the transformation of pro-inflammatory macrophages into anti-inflammatory macrophages. However, no in vivo studies have shown whether lactate can alleviate inflammation. Methods: RAW 264.7 macrophages were stimulated by LPS to induce an M1 phenotype, and cultured with low and high concentrations of lactate. The cells were then observed for phenotypic transformations and expression of inflammatory mediators and surface markers. The expression of inflammatory factors was also analyzed in the cell-free supernatant fraction. Further, a mouse model of DSS-induced colitis was established and treated with lactate. Colonic tissue injury was monitored by histopathological examinations. Results: The in vitro experiments showed that lactate promoted the transformation of activated macrophages to M2 phenotype and decreased the expression of TLR4-mediated NF-κB signaling proteins and inflammatory factors. In the DSS-induced colitis mouse model, lactate promoted the phenotypic transformation of macrophages in colonic tissue, reduced inflammation and organ damage, inhibited the activation of TLR4/NF-κB signaling pathway, decreased the serum levels of pro-inflammatory factors, increased the expression of anti-inflammatory factors, promoted the repair of the intestinal mucosal barrier and reduced the severity of colitis. Conclusions: Lactate inhibits the TLR/NF-κB signaling pathway and the production of pro-inflammatory factors by promoting polarization of macrophages. In addition, lactate promotesthe repair of the intestinal mucosal barrier and protects intestinal tissue in inflammation. Furthermore, lactate is relatively safe. Therefore, lactate is a promising and effective drug for treating inflammation through immunometabolism regulation.

Zizyphus jujuba cv. Muzao polysaccharides enhance intestinal barrier function and improve the survival of septic mice.

This study aimed to examine the role of Zizyphus jujuba cv. Muzao polysaccharides (ZJPs) in protecting intestinal barrier function and the survival of septic mice. The sepsis mouse model was generated through cecal ligation and puncture (CLP) to observe the effect of ZJPs on the function of the intestinal barrier in the context of sepsis. We observed the clinical symptoms and survival time of the mice and evaluated serum inflammatory cytokines, intestinal pathological changes and intestinal permeability. Moreover, tight junction (TJ) proteins and apoptosis-associated proteins in intestinal tissue were examined. Finally, TLR4/NF-κB pathway-related proteins were measured in all groups. The results showed that pretreatment with ZJPs improved clinical and histological scores and reduced intestinal barrier permeability, and the levels of proinflammatory factors were decreased. Pretreatment with ZJPs also upregulated the levels of TJ proteins and downregulated the expression of proapoptotic proteins. Moreover, the activation of TLR4/NF-κB signaling was partly inhibited in septic mice by ZJPs pretreatment. The current study provides evidence that ZJPs have the potential to protect intestinal barrier function and improve the survival of septic mice via the attenuation of TLR4/NF-κB inflammatory signaling. PRACTICAL APPLICATIONS: This study reports the potential protective effect of ZJPs against cecal ligation and puncture (CLP)-induced sepsis. Our data reveal that CLP induced damage to the gut mucosal barrier, inflammation, and apoptosis in intestinal tissues. However, pretreatment with ZJPs improved clinical and histological scores, reduced intestinal barrier permeability, and decreased the levels of proinflammatory factors in mice. Pretreatment with ZJPs also upregulated the levels of TJ proteins and downregulated the expression of proapoptotic proteins. Moreover, the activation of TLR4/NF-κB signaling was partly inhibited in septic mice after ZJPs pretreatment. These findings provide evidence that pretreatment with ZJPs has the potential to attenuate CLP-induced gut damage in mice by restraining inflammation and apoptosis via the attenuation of NF-κB signaling. It provides a basis for further study of ZJPs in sepsis.

Erratum: Isoliquiritigenin induces apoptosis of human bladder cancer T24 cells via a cyclin-dependent kinase-independent mechanism.

[This corrects the article DOI: 10.3892/ol.2017.6159.].

pH-Responsive Wormlike Micelles Formed by an Anionic Surfactant Derived from Rosin.

A novel pH-responsive wormlike micellar viscoelastic solution was constructed by a rosin-based anionic surfactant (Na-MPA-AZO-Na) in the presence of cetyltrimethylammonium bromide (CTAB). The viscoelasticity, aggregate morphology, and pH-responsiveness of the pH-responsive wormlike micelles have been investigated through the method of rheology and cryogenic-transmission electron microscopy. Its corresponding mechanism has been studied using 1H NMR and 1H-1H 2D NOESY HNMR. The zero-shear viscosity (η0) of the wormlike micellar solution rapidly decreases by 3 orders of magnitude as the pH increases from 5.21 to 9.56. The viscoelastic fluids and water-like solutions can be converted by tuning the pH between 3.62 and 12.00, and the corresponding aggregates also transform between wormlike micelles and spherical micelles. In addition, the wormlike micellar cross-sectional diameter is approximately 10 nm, which is remarkably larger than that of the common wormlike micelles. The phenomenon can be attributed to the large steric volume of the rosin rigid skeleton. When the pH is 12.00, a "pseudo" Gemini surfactant is constructed by Na-MPA-AZO-Na and CTAB through the electrostatic interactions. Wormlike micelles also can be formed with the increasing concentrations. The η0 of the wormlike micellar system shows strong dependence on concentration with an exponent of 9.6 (η0 ∝ C9.6). This work further promotes new applications of forest resources.

Chamaejasmin B Decreases Malignant Characteristics of Mouse Melanoma B16F0 and B16F10 Cells.

Chamaejasmin B (CHB), a natural biflavone isolated from Stellera chamaejasme L., has been reported to exhibit anti-cancer properties; however, its effect in melanoma cells is not clear. Here, we aimed to investigate the anticancer effect of CHB in mouse melanoma B16F0 and B16F10 cells. We found that CHB significantly suppressed cell proliferation and promoted cell cycle arrest at G0/G1 phase in B16F0 cells; it also induced cell differentiation and increased melanin content by increasing tyrosinase (TYR) activity and mRNA levels of melanogenesis-related genes in B16F0 cells. Meanwhile, wound closure, invasion, and migration of B16F0 and B16F10 cells were dramatically inhibited. Moreover, CHB significantly increased ROS levels and decreased ΔΨm, resulting in B16F0 and B16F10 cell apoptosis. Finally, in vivo studies showed that CHB inhibited tumor growth and induced tumor apoptosis in a mouse xenograft model of murine melanoma B16F0 and B16F10 cells. Overall, CHB decreases malignant characteristics and may be a promising therapeutic agent for malignant melanoma cells via multiple signaling pathways.

Hybrids of CO2-Responsive Water-Redispersible Single-Walled Carbon Nanotubes by a Surfactant Based on Natural Rosin.

A kind of polymerizable dispersant based on natural rosin was used to disperse single-walled carbon nanotubes (SWNTs) in aqueous solution followed by in situ free-radical polymerization to achieve a controllable SWNTs dispersion, that not only can be controlled by CO2/N2, but can also be recycled and redispersed in CO2-saturated water after drying without sonication.

Reversible dispersion and precipitation of single-walled carbon nanotubes using a pH-responsive rigid surfactant.

A pH-responsive rigid surfactant derived from rosin was used to disperse and precipitate single-walled carbon nanotubes (SWNTs) in aqueous solution. The precipitated SWNTs could be re-dispersed by changing the pH without sonication owing to the hydrophobic steric layers formed by the rigid group and π-π interactions from the azobenzene group.

CO2-Responsive Pickering Emulsions Stabilized by a Bio-based Rigid Surfactant with Nanosilica.

A novel CO2-responsive surfactant, maleopimaric acid glycidyl methacrylate ester 3-(dimethylamino)propylamine imide (MPAGN), based on sustainable resource of rosin was synthesized and used to prepare a kind of CO2-responsive Pickering emulsions with nanosilica. MPAGN can be reversibly responsive to CO2 and N2 between active cationic (MPAGNH+) and inactive nonionic (MPAGN), leading to adsorb on or desorb from the surface of nanosilica, then stabilize or break emulsion. CO2-responsive behavior of MPAGN was verified by cycle change of pH and conductivity with bubbling CO2 and N2 alternately. The type of adsorption of MPAGNH+ at the particle-water interface was explained according to the adsorption isotherms. The mechanisms of stabilization, destabilization, and restabilization of Pickering emulsion were analyzed according to zeta potentials and droplet size. This Pickering emulsion can be reversible between stable and unstable by bubbling CO2 and N2 alternately. Moreover, this emulsifier can be recycled when new oil was added after removing the initial oil. Therefore, it not only has economic benefits but also has an environmentally friendly property.

Phase Behavior and Aggregation in a Catanionic System Dominated by an Anionic Surfactant Containing a Large Rigid Group.

The phase behavior and aggregates of a catanionic system have been investigated. The anionic surfactants in the mixed systems were sodium N-alkylmaleimidepimaric carboxylate (Cn -MPA-Na, n=12, 14, 16), which were prepared from rosin and contain a large rigid skeleton and a flexible alkane chain, and the cationic surfactant was cetyltrimethylammonium bromide (CTAB). The phase behavior of the C14 -MPA-Na/CTAB system transformed sequentially from a viscoelastic solution to an aqueous surfactant two-phase system (ASTP), an aqueous surfactant three-phase system (AS3P), and an anisotropic homogeneous phase as the concentration of C14 -MPA-Na was continuously increased from 10 to 35 mm. The C16 -MPA-Na/CTAB system showed similar phase behavior, whereas the C12 -MPA-Na/CTAB system did not form the AS3P system. The corresponding microstructures in the different phases were investigated by using rheology and cryogenic transmission electron microscopy (Cryo-TEM). The aggregates in the viscoelastic solutions are thread-like, annular, and worm-like micelles. The microstructures in the upper phase of the ASTP are worm-like micelles, and in the lower phase are spherical and rod-like micelles. The aggregates in the upper and lower phases of the AS3P are worm-like micelles and spherical and rod-like micelles, respectively. The aggregates in the middle phase of the AS3P and the anisotropic homogeneous phase are sponge-like micelles. The clear Cryo-TEM images of the sponge-like micelles are presented.

Licochalcone D induces apoptosis and inhibits migration and invasion in human melanoma A375 cells.

The aim of the present study was to determine the effects of Licochalcone D (LD) on the apoptosis and migration and invasion in human melanoma A375 cells. Cell proliferation was determined by sulforhodamine B assay. Apoptosis was assessed by Hoechst 33258 and Annexin V­FITC/PI staining and JC­1 assay. Total intracellular reactive oxygen species (ROS) was examined by DCFH­DA. Wound healing and Transwell assays were used to detect migration and invasion of the cells. The activities of matrix metalloproteinase (MMP­2 and MMP­9) were assessed via gelatin zymography. Tumor growth in vivo was evaluated in C57BL/6 mice. RT­PCR, qPCR, ELISA and western blot analysis were utilized to measure the mRNA and protein levels. Our results showed that LD inhibited the proliferation of A375 and SK­MEL­5 cells in a concentration­dependent manner. After treatment with LD, A375 cells displayed obvious apoptotic characteristics, and the number of apoptotic cells was significantly increased. Pro­apoptotic protein Bax, caspase­9 and caspase­3 were upregulated, while anti­apoptotic protein Bcl­2 was downregulated in the LD­treated cells. Meanwhile, LD induced the loss of mitochondrial membrane potential (ΔΨm) and increased the level of ROS. ROS production was inhibited by the co­treatment of LD and free radical scavenger N­acetyl­cysteine (NAC). Furthermore, LD also blocked A375 cell migration and invasion in vitro which was associated with the downregulation of MMP­9 and MMP­2. Finally, intragastric administration of LD suppressed tumor growth in the mouse xenograft model of murine melanoma B16F0 cells. These results suggest that LD may be a potential drug for human melanoma treatment by inhibiting proliferation, inducing apoptosis via the mitochondrial pathway and blocking cell migration and invasion.

Annular and threadlike wormlike micelles formed by a bio-based surfactant containing an extremely large hydrophobic group.

A novel bio-based anionic surfactant containing a large rigid group and a flexible alkyl chain, namely, sodium N-dodecyl-maleimidepimaric carboxylate (C12-MPA-Na), was synthesized from rosin. The molecular structure of C12-MPA-Na was identified using 1H NMR, FT-IR spectroscopy and MS. Despite containing 36 carbon atoms, C12-MPA-Na showed good water solubility at room temperature. Large spherical aggregates with diameters of 100-200 nm were formed by C12-MPA-Na when its concentration was above 0.1 mM, which was slightly higher than the critical micelle concentration (0.078 mM). Annular wormlike micelles were discovered with increasing C12-MPA-Na concentration, and began to change into extremely long threadlike wormlike micelles when the C12-MPA-Na concentration reached approximately 58 mM. The viscoelastic properties of the wormlike micelle solutions were investigated using steady state and oscillatory shear sweep rheological measurements. The zero-shear viscosity (η0) strongly depended on the concentration of C12-MPA-Na, and the scaling exponent was 34.1. Cryo-TEM confirmed the formation of large spherical aggregates and wormlike micelles. 1H-1H 2D nuclear Overhauser effect spectroscopy (NOESY) was used to detect the molecular interactions of C12-MPA-Na. The results indicated that the alkyl chain of C12-MPA-Na was partially overlapped with its non-planar rigid structure in aqueous solution, and the possible aggregation process for C12-MPA-Na was proposed.

Isoliquiritigenin induces apoptosis of human bladder cancer T24 cells via a cyclin-dependent kinase-independent mechanism.

The aim of the present study was to investigate whether an increase in cyclin-dependent kinase 2 (CDK2) activity is involved in apoptosis of human bladder cancer T24 cells induced by isoliquiritigenin (ISL). The viability of T24 cells was estimated using a sulforhodamine B assay. Cell morphological changes were examined using Hoechst 33258 staining. The apoptotic rate was determined by staining cells with Annexin V-fluorescein isothiocyanate and propidium iodide labeling. The mitochondrial membrane potential (ΔΨm) was measured using 5,5,6,6-tetrachloro-1,1, 3,3-tetraethyl benzimidazole carbocyanine iodide. Alterations in the apoptosis-related regulators B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), Bcl-2-interacting mediator of cell death (Bim), apoptotic protease-activating facter-1 (Apaf-1), caspase-9 and caspase-3 were determined using reverse transcription-polymerase chain reaction (PCR) and quantitative PCR methods. Western blot analysis was used to detect the expression of Bcl-2, Bax and caspase-3. CDK2 activity was measured using a spectrometric assay. Following treatment with ISL (between 30 and 70 µg/ml) for 24 h, typical apoptotic morphological changes were observed in T24 cells, exhibiting an edge set of chromosomes, nuclear condensation, nuclear fragmentation and other morphological features. Treatment with ISL increased the apoptotic ratio of T24 cells in a concentration-dependent manner and induced a decrease in the ΔΨm in a time-dependent manner. Treatment with ISL upregulated the expression of Bax, Bim, Apaf-1, caspase-9 and caspase-3, downregulated the expression of Bcl-2, and increased CDK2 activity. MK-8776 (an inhibitor of CDK2) antagonized the apoptosis induced by ISL, and, compared with treatment with ISL alone, pretreatment with MK-8776 inhibited the decrease in ΔΨm, downregulated the mRNA expression of Bax, Bim, Apaf-1, caspase-9 and caspase-3, and upregulated Bcl-2 mRNA expression. Western blot analysis demonstrated that, with increasing ISL concentration, the Bcl-2 expression level was significantly decreased (P<0.05), whereas caspase-3 and Bax expression levels were significantly increased (P<0.01). These results indicated that ISL treatment caused a significant decrease in the proliferation rate and increase in apoptosis of T24 cells. The mechanism by which ISL induces T24 cell apoptosis in vitro may be associated with an increase in CDK2 activity, downregulation of the ΔΨm and activation of caspase-3/caspase-9-mediated mitochondrial apoptotic signaling pathways.

Jolkinolide B induces apoptosis and inhibits tumor growth in mouse melanoma B16F10 cells by altering glycolysis.

Most cancer cells preferentially rely on glycolysis to produce the energy (adenosine triphosphate, ATP) for growth and proliferation. Emerging evidence demonstrates that the apoptosis in cancer cells could be closely associated with the inhibition of glycolysis. In this study, we have found that jolkinolide B (JB), a bioactive diterpenoid extracted from the root of Euphorbia fischeriana Steud, induced tumor cells apoptosis and decreased the production of ATP and lactic acid in mouse melanoma B16F10 cells. Furthermore, we found that JB downregulated the mRNA expression of glucose transporter genes (Glut1, Glut3 and Glut4) and glycolysis-related kinase genes (Hk2 and Ldha) in B16F10 cells. Moreover, treatment with JB upregulated the mRNA expression of pro-apoptosis genes (Bax), downregulated the mRNA expression of anti-apoptosis genes (Bcl-2, Caspase-3 and Caspase-9), decreased the potential of mitochondrial membrane and increased reactive oxygen species (ROS) levels in B16F10 cells. Finally, intragastric administration of JB suppressed tumor growth and induced tumor apoptosis in mouse xenograft model of murine melanoma B16F10 cells. Taken together, these results suggest that JB could induce apoptosis through the mitochondrial pathway and inhibit tumor growth. The inhibition of glycolysis could play a crucial role in the induction of apoptosis in JB-treated B16F10 cells.

Isoliquiritigenin Inhibits Proliferation and Induces Apoptosis via Alleviating Hypoxia and Reducing Glycolysis in Mouse Melanoma B16F10 Cells.

BACKGROUND: Isoliquiritigenin (ISL) is a licorice chalcone. According to CN104758274, CN101658513 and US009089546, it is claimed that ISL has anti-inflammatory, anti-oxidative, and anti-tumoral effects. OBJECTIVE: This study aimed to investigate the potential therapeutic effect of ISL in mouse melanoma B16F10 cells. METHODS: Sulforhodamine B (SRB) colorimetric assay was used to test the effects of ISL on proliferation. Commercial assay kits were applied to assess glucose uptake, lactate production and ATP levels. Measurement of apoptosis was involved with Hoechst 33258, JC-1 and annexin V-FITC/PI staining. H2DCFDA probe was employed to detect ROS generation. Quantitative RT-PCR and western blot were utilized to measure the mRNA and protein levels. RESULTS: ISL abated hypoxia-inducible factor 1α (HIF-1α) stability and reduced a series of glycolysis-relevant enzymes expression, including glucose transporters 1/4 (GLUT 1/4), hexokinase 2 (HK2), pyruvate kinase M2 (PKM2) and lactate dehydrogenase A (LDHA). Exposure to ISL induced the mitochondrial membrane potential depolarization and increased intracellular reactive oxygen species (ROS) level. ISL could effectively inhibit proliferation and alleviate hypoxia in mouse melanoma B16F10 cells via inducing apoptosis and reducing the expression of significant enzymes in the glycolysis. ISL significantly inhibited B16F10 cell proliferation via inducing apoptosis, and alleviated hypoxia by recovering mitochondrial function and reversing high glycolysis. CONCLUSION: Our findings propose that ISL can be a promising therapeutic agent for the melanoma via reliving hypoxia of microenvironment and targeting energy metabolism system of cancer cells. Consistent with WO2015079213 and WO2014084494, targeting glycolysis can be an effective means to anti-cancer.

Crystal structure of 7-isopropyl-1,4a,N-trimethyl-1,2,3,4,4a,4b,5,6,7,8,10,10a-dodeca-hydro-phenanthrene-1-carb-ox-amide.

In the title compound, C26H37NO, a new derivative of di-hydro-abietic acid, the two cyclo-hexene rings adopt half chair conformations, whereas the cyclo-hexane ring has a chair conformation. Each of the methyl groups is in an axial position with respect to the tricyclic hydro-phenanthrene residue. In the crystal packing, methyl-ene-C-H⋯π(phen-yl) inter-actions lead to supra-molecular helical chains along [010]; the amide-H atom does not form a significant inter-molecular inter-action owing to steric pressure.

Antioxidative and cardioprotective effects of total flavonoids extracted from Dracocephalum moldavica L. against acute ischemia/reperfusion-induced myocardial injury in isolated rat heart.

This study evaluates antioxidative and cardioprotective effects of total flavonoids extracted from Dracocephalum moldavica L. (DML). The total flavonoids showed remarkable scavenging effects against 1,1-diphenyl-2-picrylhydrazyl, hydroxyl and superoxide anion radicals in vitro. Compared with the ischemia/reperfusion (I/R) group as demonstrated by the use of improved Langendorff retrograde perfusion technology, the total flavonoids (5 µg/mL) pretreatment improved the heart rate and coronary flow, rised left ventricular developed pressure and decreased creatine kinase, lactate dehydrogenase levels in coronary flow. The infarct size/ischemic area at risk of DML-treated hearts was smaller than that of I/R group; the superoxide dismutase activity and glutathione/glutathione disulfide ratio increased and malondialdehyde content reduced obviously (P < 0.01) in total flavonoids treatment groups. In conclusion, the total flavonoids possess obvious protective effects on myocardial I/R injury, which may be related to the improvement of myocardial oxidative stress states.

Licochalcone A inhibiting proliferation of bladder cancer T24 cells by inducing reactive oxygen species production.

The aim of this study was to determine the relationship between proliferation inhibition and the production of reactive oxygen species (ROS) induced by Licochalcone A (LCA). Cell viability was evaluated using sulforhodamine B (SRB) assay. Intracellular ROS level was assessed using the 2, 7-dichlorofluorescein diacetate (H2DCFDA) probe and dihydroethidium (DHE) probe assay. The results indicate that LCA inhibits human bladder cancer T24 proliferation in a concentration-dependent manner, with an IC50 value of approximately 55 µM. The LCA-induced ROS production is inhibited by the co-treatment of LCA and free radical scavenger N-acetyl-cysteine (NAC), on the contrary, the proliferation rate and ROS production increase when treated by the combination of LCA and L-buthionine-(S,R)-sulfoximine (BSO). The ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) decreases in a concentration-dependent manner. The results suggest that LCA inhibits proliferation by increasing intracellular ROS levels resulted in an oxidative stress status in T24 cells.