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The effects of differentiated cells on stem cell differentiation were analyzed by co-culture using a cell-encapsulated double-layered hydrogel system. As a polymer hydrogel matrix, a water-soluble zwitterionic polymer having both 2-methacryloyloxyethyl phosphorylcholine unit and p-phenylboronic acid unit (PMBV), was complexed spontaneously with poly(vinyl alcohol) (PVA) under mild cell culture conditions. The elastic modulus of the hydrogel was controlled by changing the composition of the polymer in the solution. Mouse mesenchymal stem cells (MSCs), C3H10T1/2 cells, were encapsulated into PMBV/PVA hydrogels and cultured. In the PMBV/PVA hydrogel with a lower creep modulus (0.40 kPa), proliferation of C3H10T1/2 cells occurred, and the formation of cell aggregates was observed. On the other hand, a higher creep modulus (1.7 kPa) of the hydrogel matrix prevented cell proliferation. Culturing C3H10T1/2 cells encapsulated in PMBV/PVA hydrogel in the presence of bone morphogenetic protein-2 increased the activity of intracellular alkaline phosphatase (ALP). This indicated that C3H10T1/2 cells differentiated into mature osteoblasts. When the C3H10T1/2 cells encapsulated in the PMBV/PVA hydrogel were cultured in combination with the mature osteoblasts in the hydrogel by a closed contacting double-layered hydrogel structure, higher ALP activity was observed compared with the cells cultured separately. It was considered that the differentiation of C3H10T1/2 cells in the hydrogel layer was induced by cytokines diffused from mature osteoblasts encapsulated in another hydrogel layer. It could be concluded that the PMBV/PVA hydrogel system provides a good way to observe the effects of surrounding cells on cell function in three-dimensional culture.

Chronic skin ulcers are a primary global health problem. Velvet antler polypeptide (VAP) regulates endothelial cell migration and angiogenic sprout. Adipose-derived stem cells (ADSCs) are reported to make pivotal impacts upon wound healing. This study aimed to explore the role of VAP combined with ADSCs in wound healing of chronic skin ulcers. The effect of VAP on phenotypes of ADSCs, and VAP (PLGA microspheres) combining with ADSCs on wound healing of chronic skin ulcers in vivo was evaluated. VAP generally promoted the proliferation, migration and invasion of ADSCs, and ADSC-induced angiogenesis in human umbilical vein endothelial cells (HUVECs) through PI3K/Akt/HIF-1α pathway. VAP-PLGA (PLGA microspheres) enhanced the promoting effect of ADSCs on wound healing, pathological changes, and angiogenesis in chronic skin ulcers in vivo. VAP-PLGA intensified the effect of ADSCs on up-regulating the levels of p-PI3K/PI3K, p-Akt/Akt, HIF-1α, vascular endothelial growth factor (VEGF), stromal cell-derived factor-1 (SDF-1), C-X-C motif chemokine receptor 4 (CXCR4), angiopoietin-4 (Ang-4), VEGF receptor (VEGFR), and transforming growth factor-β1 (TGF-β1), and down-regulating the levels of interleukin-1 β (IL-1β), IL-18 and IL-6 in wound tissues in chronic skin ulcers in vivo. Collectively, VAP promoted the growth, migration, invasion, and angiogenesis of ADSCs through activating PI3K/Akt/HIF-1α pathway, and VAP-PLGA enhanced the function of ADSCs in promoting wound healing in vivo, which was associated with angiogenesis, inflammation inhibition, and dermal collagen synthesis.

Hospitalized preterm infants experience painful medical procedures. Oral sucrose is the nonpharmacological standard of care for minor procedural pain relief. Infants are treated with numerous doses of sucrose, raising concerns about potential long-term effects. The objective of this study was to determine the long-term effects of neonatal oral sucrose treatment on growth and liver metabolism in a mouse model. Neonatal female and male mice were randomly assigned to one of two oral treatments ( n = 7–10 mice/group/sex): sterile water or sucrose. Pups were treated 10 times/day for the first 6 days of life with 0.2 mg/g body wt of respective treatments (24% solution; 1–4 μL/dose) to mimic what is given to preterm infants. Mice were weaned at age 3 wk onto a control diet and fed until age 16 wk. Sucrose-treated female and male mice gained less weight during the treatment period and were smaller at weaning than water-treated mice ( P ≤ 0.05); no effect of sucrose treatment on body weight was observed at adulthood. However, adult sucrose-treated female mice had smaller tibias and lower serum insulin-like growth factor-1 than adult water-treated female mice ( P ≤ 0.05); these effects were not observed in males. Lower liver S-adenosylmethionine, phosphocholine, and glycerophosphocholine were observed in adult sucrose-treated compared with water-treated female and male mice ( P ≤ 0.05). Sucrose-treated female, but not male, mice had lower liver free choline and higher liver betaine compared with water-treated female mice ( P < 0.01). Our findings suggest that repeated neonatal sucrose treatment has long-term sex-specific effects on growth and liver methionine and choline metabolism.

Oleosin is a hydrophobic protein that punctuates the surface of plant seed lipid droplets, which are 20 nm-100 μm entities that serve as reservoirs for high-energy metabolites. Oleosin is purported to stabilize lipid droplets, but its exact mechanism of stabilization has not been established. Probing the structure of oleosin directly in lipid droplets is challenging due to the size of lipid droplets and their high degree of light scattering. Therefore, a medium in which the native structure of oleosin is retained, but is also amenable to spectroscopic studies is needed. Here, we show, using a suite of biophysical techniques, that dodecylphosphocholine micelles appear to support the tertiary structure of the oleosin protein (i.e., hairpin conformation) and render the protein in an oligomeric state that is amenable to more sophisticated biophysical techniques such as NMR.

Global transcriptional regulators are prevalent in gram-positive pathogens. The transcriptional regulators of the Mga/AtxA family regulate target gene expression by directly binding to the promoter regions, that results in the coordinated expression of virulence factors. The spd_1587 gene of Streptococcus pneumoniae strain D39 encodes MgaSpn, which shares sequence similarity with global transcriptional regulators of the Mga/AtxA family. In this study, we demonstrated that MgaSpn regulates the biosynthesis of the capsule and phosphorylcholine, which play key roles in disease severity in S. pneumoniae infections. MgaSpn directly binds to the cps and lic1 promoters and affects the biosynthesis of the capsule and phosphorylcholine. MgaSpn binds to two specific sites on the promoter of cps, one of which contains the −35 box of the promoter, with high affinity. Consistently, low-molecular-weight capsule components were observed in the mgaSpn-null mutant strain. Moreover, we found that phosphorylcholine content was notably increased in the unencapsulated mgaSpn mutant strain. The mgaSpn null mutant caused more severe systemic disease than the parental strain D39. These findings indicate that the pneumococcal MgaSpn protein can inhibit capsule and phosphorylcholine production, thereby affecting the virulence of S. pneumoniae.

Herein, the postfunctionalization of different non-fouling PISA particles, prepared from either poly(oligo ethylene glycol methyl ether methacrylate) (pPEGMA) and the anticancer drug PENAO (4-(N-(S-penicillaminylacetyl)amino)phenylarsenonous acid) or zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC) and PENAO were reported. Both PISA particles were reacted with triphenylphosphonium (TPP) as mitochondria targeting units in order to evaluate the changes in cellular uptake or the toxicity of the conjugated arsenic drug. Attachment of TPP onto the PISA particles however was found not to enhance the mitochondrial accumulation, but it did influence overall the biological activity of pMPC-based particles in 2D and 3D cultured sarcoma SW982 cells. When TPP was conjugated to the pMPC PISA particles more cellular uptake as well as better spheroid penetration were observed, while TPP on PEG-based PISA had only little effect. It was hypothesized that TPP on the micelle surface may not be accessible enough to allow mitochondria targeting, but more structural investigations are required to elucidate this.

BACKGROUND: One crucial factor in skin tissue engineering is to understand the hydration and barrier property of skin. We investigated the skin hydration and stabilization strategy of inter-lamellar structure of stratum corneum (SC) using poly (2-methacryloyloxyethyl phosphorylcholine) (PMPC). METHODS: The unique hydration and stabilization potency of PMPC on the barrier function of the SC examined using freshly excised hairless mouse skin as a model membrane and the relationship between the stabilization of the lipid lamellar bilayer (LLB) and its enhanced water holding capacity was established. RESULTS: Differential scanning calorimeter based on the phase-transition temperature of lipid domain of SC demonstrated that PMPC stabilized the LLB. The ratio of the heat of lipid phase transition (△H) of SC exposed to water and PMPC for 24 h was 1.51. X-ray crystallography showed the presence of well- organized lipids in intercellular membranes exhibiting short and long periodicity of lamellar phases. The peak at 4.4 nm attributed to the long periodicity phase (LPP) was missing in water-treated SC, where, the presence of 4.2- 4.4 nm peak in PMPC treated SC indicated that PMPC stabilized LPP. Transmission electron microscopy study demonstrated that the LLB structure became more rigid and orderly in PMPC treated SC. CONCLUSION: The unique ion paired structure of PMPC enhances the barrier function of the SC by stabilizing LLB structure and hydration by inducing weakly bound water. The unique hydration state and stabilization effect from extended water exposure could provide a valuable information to prepare reliable artificial skin matrix and skin tissue. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13770-021-00379-4.

Exploring structural behavior of pure 1-palmitoyl-2-stearoyl-sn-glycero-3-phosphocholine (PSPC) and multicomponent PSPC and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N[amino(poly(ethylene glycol))-2000] (DSPE-PEG2000) membranes and their interaction with pharmaceutically important drugs carry huge importance in drug delivery. Using all-atom molecular dynamics (MD) simulations, we investigated the phase behavior of pure and PEGylated membranes at the temperature range of 280-360 K. We observe a gel-to-liquid crystalline phase transition for pure PSPC between 320 and 330 K, and in the case of multicomponent membranes, at 320 K, a coexistence of order-disorder phases is observed, which gradually transform to a complete liquid crystalline to gel phase between 320 and 310 K. We further studied the interaction of Paclitaxel with pure PSPC and PEGylated bilayers and elucidated the interaction behavior of Paclitaxel at the bilayer interfaces. Understanding of structural and interaction behaviors of the PEGylated bilayers with Paclitaxel will help to explore Paclitaxel-based drug applications in the future.

Backgrounds: Transforming growth factor (TGF)-β is shown to play a critical role in cancer progression by inducing epithelial mesenchymal transition (EMT). Polyinosinic-polycytidylic acid (polyI:C), a synthetic agonist for toll-like receptor (TLR) 3, has been successfully used to treat some cancer patients as a vaccine adjuvant, but its direct action on the proliferation or migration of cancer cells, such as lung cancer cells, undergoing EMT remains unknown. Methods and results: By an in vitro cell proliferation assay, polyI:C showed no effect on the growth of TGF-β1-treated A549 human lung cancer cells at the concentration range up to 10 mg/ml; however, it markedly suppressed the motility in a cell scratch and a cell invasion assay. By Western blotting, polyI:C dramatically decreased TGF-β1-induced Ak strain transforming (Akt) phosphorylation and increased phosphatase and tensin homologue (PTEN) expression without affecting the Son of mothers against decapentaplegic (Smad) 3 phosphorylation or the expression level of E-cadherin, N-cadherin or Snail, indicating that polyI:C suppressed cell motility independently of the ‘cadherin switching’. The Akt inhibitor perifosine inhibited TGF-β1-induced cell invasion, and the PTEN-specific inhibitor VO-OHpic appeared to reverse the inhibitory effect of polyI:C. Conclusion: Our results indicate that polyI:C has the capacity to suppress the motility of TGF-β1-treated A549 cells by targeting the phosphatidylinositol 3-kinase /Akt pathway partly via PTEN and suggest that polyI:C may be used to prevent or reduce the metastasis of lung cancer cells.

In this work we report a lipidomics approach to study the effects of two diet systems on the composition of ovine milk. Milk from two groups of Sarda sheep grazing on 40% (P40) and 60% (P60) of pasture were analyzed by a UHPLC-QTOF-MS analytical platform and data submitted to multivariate statistical analysis. Pairwise partial least square discriminant analysis of the lipid profile of the data was carried out to classify samples and to find discriminant lipids. The two dietary groups were characterized by differences in triacylglycerols, phosphocholines and phosphatidylethanolamines levels. Discriminants of the P40 group were TG and PC containing in their backbone saturated medium chain FA thus suggesting greater de novo fatty synthesis in the mammary gland. On the other hand, the P60 group was characterized by TG and PC formed by unsaturated long chain FA originating from the diet or from lipid mobilization.

Violent inflammation has impeded worry-free application of polypropylene (PP) hernia meshes. Efficient anti-inflammatory coatings are urgently needed to alter the situation. Here, we present a zipper-like, two-layer coating with an intermediate antioxidant layer (I) and an outer antifouling layer (II) to endow PP meshes with synergistic anti-inflammatory effects. The controllable antioxidant ability of layer I was obtained by modulating the assembly cycle of the metal-phenolic network (MPN) composed of tannic acid (TA) and Fe3+. Polyzwitterionic (PMAD) brush-based layer II was generated upon multiple interactions between the catechol side groups of PMAD and layer I. To consolidate the entire assembly architecture, aryloxy radical coupling was initiated through alkali-catalyzed oxidation. The reaction is similar to a "zipping up" process to construct covalent bonds in the I-II interface and layer I by coupling adjacent catechol groups, which facilely achieved grafting and cross-linking. The obtained coating (PMAD-TA/Fe) did not affect the original properties of the PP mesh and remained stable during cyclic tensile testing or degradation. Most importantly, the excellent antioxidant and antifouling capacities enabled PMAD-TA/Fe-PP to exhibit desirable anti-inflammatory effects and reduce collagen deposition when compared with the bare material. The synergistic anti-inflammatory coating eliminates a major hindrance in the design of biocompatible meshes, and its potential application in developing medical implants with low immunogenicity is promising.

Choline phosphate lipids have been designed and developed as new-generation zwitterionic nanocarriers with excellent biocompatibility and bioorthogonality to provide a more programmable performance for cancer therapy. However, there is a lack of spatiotemporal and reversible control for drug release at target tumor cells, which can lead to severe adverse effects to normal tissue and discounted treatment outcome. Here, light-inducible Lip-cRGDfk/ICG/Dox liposomes were developed for synergistic cancer therapy. ICG can effectively convert light energy into selective heating in a local environment upon laser irradiation, thus inducing thermal ablation of tumor cells, and further reversibly trigger the spatiotemporal release of anticancer drugs (Dox) at tumor cells due to the conformation transformation of CP lipids to synergistically kill tumor cells. That Lip-cRGDfk/ICG/Dox exhibited a significant improvement for breast cancer therapy in vitro and in vivo is also demonstrated, thus it can serve as an efficient platform to noninvasively and spatiotemporally control the activation of cytotoxicity at tumor cells for precision cancer therapy.

Mesocotyl elongation of rice is crucial for seedlings pushing out of deep soil. The underlying mechanisms of phospholipid signaling in mesocotyl growth of rice are elusive. Here we report that the rice non-specific phospholipase C6 (OsNPC6) is involved in mesocotyl elongation. Our results indicated that all five OsNPCs (OsNPC1, OsNPC2, OsNPC3, OsNPC4 and OsNPC6) hydrolyzed the substrate phosphatidylcholine to phosphocholine (PCho), and all of them showed plasma membrane localization. Overexpression (OE) of OsNPC6 produced plants with shorter mesocotyls compared to those of Nipponbare and npc6 mutants. Although the mesocotyl growth of npc6 mutants was not much affected without gibberellic acid (GA)3, it was obviously elongated by treatment with GA. Upon GA3 treatment, SLENDER RICE1 (SLR1), the DELLA protein of GA signaling, was drastically increased in OE plants; by contrast, the level of SLR1 was found decreased in npc6 mutants. The GA-enhanced mesocotyl elongation and the GA-impaired SLR1 level in npc6 mutants were attenuated by the supplementation of PCho. Further analysis indicated that the GA-induced expression of phospho-base N-methyltransferase 1 in npc6 mutants was significantly weakened by the addition of PCho. In summary, our results suggest that OsNPC6 is involved in mesocotyl development via modulation of PCho in rice.

In the present study, water-soluble molecular complexes between carboxylic acid-functionalized multiwalled carbon nanotubes (MWCNTs) and biocompatible poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) were prepared by hand grinding. MWCNTs could be solubilized in phosphate-buffered saline using this simple method. The suspended concentration of MWCNTs was found to increase with increasing polymer concentration and pH of the solution. Heat generation from the complexes was studied upon irradiation with near-infrared (NIR) radiation at a wavelength of 808 nm. The results demonstrated that MWCNTs absorbed light and generated heat when the molecular complex was irradiated by NIR. The solution temperature increased with increasing MWCNT concentration and irradiation time. This study presents a facile method for preparation of water-soluble molecular complexes between carboxylic acid-functionalized multiwalled carbon nanotube and poly(2-methacryloyloxyethyl phosphorylcholine) (MWCNTs/PMPC) by hand grinding. MWCNTs could be solubilized in aqueous environment with higher suspended concentrations when increasing polymer concentration and pH of the solution. MWCNTs/PMPC adsorbed light and induced heat generation to reach the temperature required for photothermal therapy (PTT) when the complexes were irradiated by near-infrared (NIR) at a wavelength of 808 nm. The water-soluble MWCNT complex covered by biocompatible PMPC is a promising candidate for PTT application.

Guo Yu, 1 Zakir Ali, 2 Anam Sajjad Khan, 2 Kalim Ullah, 3 Humzah Jamshaid, 2 Alam Zeb, 4 Muhammad Imran, 4 Sadia Sarwar, 4 Han-Gon Choi, 5 Fakhar ud Din 2 1Department of Head and Neck Breast, Xinxiang Central Hospital, The Fourth Clinical College of Xinxiang Medical University, Xinxiang City, Henan Province, 453000, People’s Republic of China; 2Nanomedicine Research Group, Department of Pharmacy, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, 45320, Pakistan; 3Department of Zoology, Kohat University of Science & Technology, Kohat, Khyber Pakhtunkhwa, Pakistan; 4Riphah Institute of Pharmaceutical Sciences, Riphah International University, Islamabad, Pakistan; 5College of Pharmacy & Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, South KoreaCorrespondence: Fakhar ud Din Tel +92 512-90644314Fax +92 512-90644144Email fudin@qau.edu.pkHan-Gon Choi Email hangon@hanyang.ac.krBackground: The purpose of this study was to investigate the suitability of nanostructured lipid carriers (NLCs) loaded with miltefosine (HePC) as an anticancer drug for the treatment of breast cancer.Methods: HePC-NLCs were prepared using a microemulsion technique and then evaluated for particle size, polydispersity index (PDI), incorporation efficiency, in vitro release of entrapped drug, and hemolytic potential. Furthermore, pharmacokinetic, biodistribution, and liver toxicity analyses were performed in Sprague–Dawley rats, and antitumor efficacy was evaluated in Michigan Cancer Foundation-7 (MCF-7) and squamous cell carcinoma-7 (SCC-7) cells in vitro and in tumour-bearing BALB/c mice in vivo. Advanced analyses including survival rate, immunohistopathology, and terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assays were performed to evaluate apoptosis in vivo.Results: The average particle size of the HePC-NLCs was 143 ± 16 nm, with a narrow PDI (0.104 ± 0.002), and the incorporation efficiency was found to be 91 ± 7%. The NLCs released HePC in a sustained manner, and this release was significantly lower than that of free drug. The in vitro hemolytic assay demonstrated a significantly reduced hemolytic potential (∼ 9%) of the NLCs compared to that of the test formulations. The HePC-NLCs demonstrated enhanced pharmacokinetic behaviour over free drug, including extended blood circulation and an abridged clearance rate in rats. Furthermore, the HePC-NLCs exhibited higher cytotoxicity than the free drug in MCF-7 and SCC-7 cells. Moreover, the HePC-NLCs showed significantly enhanced (P < 0.005) antitumor activity compared to that of the control and free drug-treated mouse groups. Tumour cell apoptosis was also confirmed, indicating the antitumor potential of the HePC-NLCs.Conclusion: These findings demonstrate the ability of NLCs as a drug delivery system for enhanced pharmacokinetic, antitumor, and apoptotic effects, most importantly when loaded with HePC.Keywords: breast cancer, miltefosine, nano lipid carriers, bioavailability, pharmacokinetics, antitumor efficacy

Among zwitterionic structures, the choline phosphate (CP) group is uniquely attractive for its ability to access novel chemical compositions that embed functional groups directly into the zwitterionic moiety. This paper describes the attachment of fluorinated alkyl groups to CP moieties, yielding zwitterionic monomers

Background Despite high HIV co-infection prevalence in Ethiopian visceral leishmaniasis (VL) patients, the adequacy of antileishmanial drug exposure in this population and effect of HIV-VL co-morbidity on pharmacokinetics of antileishmanial and antiretroviral (ARV) drugs is still unknown. Methods HIV-VL co-infected patients received the recommended liposomal amphotericin B (LAmB) monotherapy (total dose 40 mg/kg over 24 days) or combination therapy of LAmB (total dose 30 mg/kg over 11 days) plus 28 days 100 mg/day miltefosine, with possibility to extend treatment for another cycle. Miltefosine, total amphotericin B and ARV concentrations were determined in dried blood spots or plasma using LC–MS/MS. Results Median (IQR) amphotericin B Cmax on Day 1 was 24.6 μg/mL (17.0–34.9 μg/mL), which increased to 40.9 (25.4–53.1) and 33.2 (29.0–46.6) μg/mL on the last day of combination and monotherapy, respectively. Day 28 miltefosine concentration was 18.7 (15.4–22.5) μg/mL. Miltefosine exposure correlated with amphotericin B accumulation. ARV concentrations were generally stable during antileishmanial treatment, although efavirenz Cmin was below the 1 μg/mL therapeutic target for many patients. Conclusions This study demonstrates that antileishmanial drug exposure was low in this cohort of HIV co-infected VL patients. Amphotericin B Cmax was 2-fold lower than previously observed in non-VL patients. Miltefosine exposure in HIV-VL co-infected patients was 35% lower compared with adult VL patients in Eastern Africa, only partially explained by a 19% lower dose, possibly warranting a dose adjustment. Adequate drug exposure in these HIV-VL co-infected patients is especially important given the high proportion of relapses.

The development and application of natural antibacterial materials have always been the focus of biomedical research. Borneol as a natural antibacterial compound has received extensive attention. However, the hydrophobicity caused by its unique structure limits its application range to a certain extent. In this study, we combine zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC) with a complex bicyclic monoterpene structure borneol compound and prepare an excellent antifouling and antibacterial surface via the Schiff-base bond. The prepared coating has excellent hydrophilicity verified by the contact angle (CA), and its polymer layer is confirmed by X-ray photoelectron spectroscopy (XPS). The zwitterion MPC and borneol moieties in the copolymer play a coordinating role, relying on super hydration and the special stereochemical structure to prevent protein adsorption and inhibit bacterial adhesion, respectively, which are demonstrated by bovine serum albumin (BSA) adsorption and antibacterial activity test. Moreover, the water-soluble borneol derivative as the antibacterial surfaces we designed here was biocompatible toward MRC-5 (lung fibroblasts), as showed by in vitro cytotoxicity assays. Such results indicate the potential application of the as-prepared hydrophilic surfaces in the biomedical materials.

Background: Atherosclerosis is an inflammatory disease involving activation of adaptive and innate immune responses to antigens, including oxidized low-density lipoprotein (oxLDL) and phosphorylcholine (PC). Dendritic cells (DCs), which are antigen-presenting cells that activate T cells, are present in atherosclerotic lesions and are activated in immune organs. However, the mechanism by which PC promotes atherosclerosis is unclear. Methods and Results: To evaluate whether PC promotes atherosclerosis via DCs, 2×105 DCs activated by PC-keyhole limpet hemocyanin (DCs+PC-KLH) were injected into ApoE-/- mice and the features of the plaques and the effects of the DCs on cellular and humoral immunity against PC-KLH were determined. Mice injected with DCs+PC-KLH had significantly larger atherosclerotic lesions than controls, with increased inflammation in the lesions and plaque instability. Furthermore, DCs+PC-KLH were characterized using flow cytometry after coculture of bone marrow-derived DCs and naive T cells. DCs+PC-KLH showed an inflammatory phenotype, with increased CD86, CD40, and major histocompatibility complex Class II molecules (MHC-II), which promoted PC-specific T helper (Th) 1 and Th17 cell differentiation in vivo and in vitro. Moreover, 2 weeks after the administration of DCs+PC-KLH to mice, these mice produced PC- and oxLDL-specific IgG2a, compared with no production in the controls. Conclusions: These findings suggest that DCs presenting PC promote specific immunity to PC, increase lesion inflammation, and accelerate atherosclerosis, which may explain how PC promotes atherosclerosis.

Significance Contact lens (CL) wearing may cause discomfort and eye dryness. We describe here the efficacy of a synthetic polymer in protecting both the corneal epithelial cells and the CL from desiccation damage. Artificial tears containing this polymer might be helpful to treat or prevent ocular surface damage in CL wearers. Purpose We aimed to investigate the protective effects of the synthetic polymer 2-methacryloyloxyethyl phosphorylcholine (poly-MPC) on corneal epithelial cells and CLs subjected to desiccation damage. Methods The interaction of poly-MPC with the cell membrane was evaluated on human primary corneal epithelial cells (HCE-F) by the sodium dodecyl sulfate damage protection assay or the displacement of the cell-binding lectin concanavalin A (ConA). Survival in vitro of HCE-F cells and ex vivo of porcine corneas exposed to desiccating conditions after pre-treatment with poly-MPC or hyaluronic acid (HA), hypromellose (HPMC), and trehalose was evaluated by a colorimetric assay. Soft CLs were soaked overnight in a solution of poly-MPC/HPMC and then let dry in ambient air. Contact lens weight, morphology, and transparency were periodically registered until complete dryness. Results Polymer 2-methacryloyloxyethyl phosphorylcholine and HPMC were retained on the HCE-F cell membrane more than trehalose or HA. Polymer 2-methacryloyloxyethyl phosphorylcholine, HA, and HPMC either alone or in association protected corneal cells from desiccation significantly better than did trehalose alone or in association with HA. Contact lens permeation by poly-MPC/HPMC preserved better their shape and transparency than did saline. Conclusions Polymer 2-methacryloyloxyethyl phosphorylcholine coats and protects corneal epithelial cells and CLs from desiccation damage more efficiently compared with trehalose and as good as other reference compounds.

Tumor microenvironment has been widely utilized for advanced drug delivery in recent years, among which hypoxia-responsive drug delivery systems have become the research hotspot. Although hypoxia-responsive micelles or polymersomes have been successfully developed, a type of hypoxia-degradable nanogel has rarely been reported and the advantages of hypoxia-degradable nanogel over other kinds of degradable nanogels in tumor drug delivery remain unclear. Herein, we reported the synthesis of a novel hypoxia-responsive crosslinker and the fabrication of a hypoxia-degradable zwitterionic poly(phosphorylcholine)-based (HPMPC) nanogel for tumor drug delivery. The obtained HPMPC nanogel showed ultra-long blood circulation and desirable immune compatibility, which leads to high and long-lasting accumulation in tumor tissue. Furthermore, HPMPC nanogel could rapidly degrade into oligomers of low molecule weight owing to the degradation of azo bond in hypoxic environment, which leads to the effective release of the loaded drug. Impressively, HPMPC nanogel showed superior tumor inhibition effect both in vitro and in vivo compared to the reduction-responsive phosphorylcholine-based nanogel, owing to the more complete drug release. Overall, the drug-loaded HPMPC nanogel exhibits a pronounced tumor inhibition effect in a humanized subcutaneous liver cancer model with negligible side effects, which showed great potential as nanocarrier for advanced tumor drug delivery., Graphical abstract HPMPC nanogel shows ultra-long blood circulation without causing the accelerated blood clearance phenomenon, which leads to enhanced accumulation in tumor tissue. HPMPC nanogel holds the drug firmly in blood or normal tissue whereas releases the drug effectively in tumor environment, leading to improved therapeutic effect and negligible side effects.Image 1

The occurrence of osteoarthritis is closely related to progressive and irreversible destruction of the articular cartilage, which increases the friction significantly and causes further inflammation of the joint. Thus, a scaffold for articular cartilage defects should be developed via lubrication restoration and drug intervention. In this study, we successfully synthesized gelatin-based composite hydrogels, namely GelMA-PAM-PMPC, with the properties of biomimetic lubrication and sustained drug release by photopolymerization of methacrylic anhydride modified gelatin (GelMA), acrylamide (AM), and 2-methacryloyloxyethyl phosphorylcholine (MPC). Tribological test showed that the composite hydrogels remarkably enhanced lubrication due to the hydration lubrication mechanism, where a tenacious hydration shell was formed around the zwitterionic phosphocholine headgroups. In addition, drug release test indicated that the composite hydrogels efficiently encapsulated an anti-inflammatory drug (diclofenac sodium) and achieved sustained release. Furthermore, the in vitro test revealed that the composite hydrogels were biocompatible, and the mRNA expression of both anabolic and catabolic genes of the articular cartilage was suitably regulated. This indicated that the composite hydrogels could effectively protect chondrocytes from inflammatory cytokine-induced degeneration. In summary, the composite hydrogels that provide biomimetic hydration lubrication and sustained local drug release represent a promising scaffold for cartilage defects in the treatment of osteoarthritis.

Our study is to understand the mechanism of ceramide production, then depletion of cholesterol and relative structural changes in supported raft bilayers using fluorescence microscopy. We worked with 5 nm thick supported raft bilayers of various compositions prepared by vesicle fusion method. The supported raft bilayers were treated with sphingomyelinase to understand hydrolysis of sphingomyelin at 37 °C and higher temperatures. We wanted to explore if the hydrolysis of sphingomyelin would produce ceramide and/or any other molecules. We were interested in knowing, what would be the structural changes in the raft bilayer due to reorganization of lipid molecules upon production of ceramide and other molecules? After the hydrolysis reaction, we saw bright spots and black patches on entire raft bilayer sample after production and reorganization. These bright spots were reversible three dimensional caps with the existing bilayer, which were proven by Fluorescence Recovery after Photo-bleaching. This concludes that excess molecules are present in the resultant bilayer, the heterogeneity of bilayer structure has resulted due to production of two molecules from single sphingomyelin i.e., phosphorylcholine and ceramide which are formed by cleavage SM making the bilayer rich in molecules. The heterogeneity might have resulted because of phase separation of cholesterol from ceramide. Since, they do not coexist as ceramide displaces cholesterol.

In this paper, we report the synthesis and characterization of novel peptide based hybrid graft copolymers that can form injectable hydrogels. These hybrid graft copolymers are composed of a biocompatible poly(2-methacryloyloxyethyl phosphorylcholine) main chain and self-assembling oligoalanine-block-poly(ethylene glycol) grafts (grafting ratio (m) = 6, 10, 20, 28, 32, and 40%), which are readily synthesized using a macromonomer by combining the solid phase peptide synthesis and conventional radical polymerization methods. Conformational analyses under a wide range of dilute aqueous solutions (pH 3–10 and 4–70 °C) revealed stable β-sheet formation. With an increase in solution concentration, the graft copolymers, except those with a low grafting ratio of m = 6, formed hydrogels displaying shear-thinning and self-healing behaviors because of the reversible self-assembly property of peptide grafts. Interestingly, the mechanical properties of hybrid graft copolymers were strongly dependent on the grafting density of the hybrid copolymers. Thus, it was observed that an increase in grafting ratio strengthened the inter-polymer network. These features enabled the graft-type hybrids to be used as injectable hydrogels for 3D cell scaffolds and controlled-release applications.

Poly(ethylene glycol) (PEG) is frequently used for liposomal surface modification. However, as PEGylated liposomes are cleared rapidly from circulation upon repeated injections, substitutes of PEG are being sought. We focused on a water-soluble polymer composed of 2-methacryloyloxyethyl phosphorylcholine (MPC) units, and synthesized poly(MPC) (PMPC)-conjugated lipid (PMPC-lipid) with degrees of MPC polymerization ranging from 10 to 100 (calculated molecular weight: 3 to 30 kDa). In addition, lipids with three different alkyl chains, myristoyl, palmitoyl, and stearoyl, were applied for liposomal surface coating. We studied the interactions of PMPC-lipids with plasma albumin, human complement protein C3 and fibrinogen using a quartz crystal microbalance with energy dissipation, and found that adsorption of albumin, C3 and fibrinogen could be suppressed by coating with PMPC-lipids. In particular, the effect was more pronounced for PMPC chains with higher molecular weight. We evaluated the size, polydispersity index, surface charge, and membrane fluidity of the PMPC-lipid-modified liposomes. We found that the effect of the coating on the dispersion stability was maintained over a long period (98 days). Furthermore, we also demonstrated that the anti-PEG antibody did not interact with PMPC-lipids. Thus, our findings suggest that PMPC-lipids can be used for liposomal coating.

To prevent tumor reproduction and metastasis, a method to modify the membranes of cancer cells was designed to suppress their vitality. A phosphatidyl choline reversed choline phosphate lipid (CP-Lip) was synthesized and modified with a PD-L1 antibody (CP-αPDL). Drug-loaded nanoparticles of CP-Lip/CP-αPDL (Dox@tCP-Lipos) could be selectively attached to melanoma cells, thus causing CP-Lip to be inserted and to interact strongly with the cell membrane, which largely reduced the fluidity and functionality of the membrane. As a result, the metabolism, reproduction, and migration of melanoma cells were proved to be weakened by CP-Lip and the tumor was 100% suppressed after treatment with Dox@tCP-Lipos.

A rational-based process was adopted for repurposing pyrrolidine-based 3-deoxysphingosylphosphorylcholine analogs bearing variable acyl chains, different stereochemical configuration and/or positional relationships. Structural features were highly influential on activity. Amongst, enantiomer 1e having 1,2-vicinal relationship for the -CH2O- and the N-acyl moieties, a saturated palmitoyl chain and an opposite stereochemical configuration to natural sphingolipids was the most potent hit compound against promastigotes showing IC50 value of 28.32 µM. The corresponding enantiomer 1a was 2-fold less potent showing a eudismic ratio of 0.54 in promastigotes. Compounds 1a and 1e inhibited the growth of amastigotes more potently relative to promastigotes. Amongst, enantiomer 1a as the more selective and safer. In silico docking study using a homology model of Leishmania donovani inositol phosphoceramide synthase (IPCS) provided plausible reasoning for the molecular factors underlying the found activity. Collectively, this study suggests compounds 1a and 1e as potential hit compounds for further development of new antileishmanial agents.

Controlling the particle structure of tumor-targeting nanomedicines in vivo remains challenging but must be achieved to control their in vivo fate and functions. Molecular bottlebrushes (MBs), where brush side chains are densely grafted from a main chain, have recently received attention as building blocks of polymer-based prodrugs because their rigid structure would be expected to demonstrate high structural stability in vivo. Here, we synthesized a poly(methacryloyloxyethyl phosphorylcholine) (pMPC)-grafted molecular bottlebrush (PCMB) conjugated with a cancer drug, doxorubicin (DOX), via an acid-cleavable hydrazone bond. A pMPC-based linear polymer (LP) conjugated with DOX was also prepared for comparison. We confirmed the lack of structural transition in the PCMB between before and after conjugation with DOX using small-angle light and X-ray scattering techniques, whereas the structure of LP was significantly influenced by DOX conjugation and transformed from a random-coil structure to a large agglomerate via hydrophobic interactions among DOXs. Although PCMB-DOX and LP-DOX showed comparable tissue permeability, pharmacokinetics, and ability to accumulate in tumor tissues, the antitumor efficacy of PCMB-DOX was better than that of LP-DOX. This was presumably due to the formation of LP-DOX agglomerates. The diffusion of cleaved DOX would be restricted in the hydrophobic core of the agglomerate, resulting in the DOX release at the tumor site being compromised. In contrast to LP-DOX, DOX release from PCMB-DOX was not compromised after accumulation in tumor tissues because it did not form such an agglomerate, resulting in the strong antitumor effect. We have demonstrated the potential of MBs as building blocks of drug carriers and believe that these findings can contribute to the design of polymer-based nanomedicines.

In this work, molecular dynamics simulations were applied to investigate the influence of lipid composition of the model membrane on the insertion of glyphosate (in its charged state, GLYP2-). The profiles of free energy, entropy and enthalpy were obtained through umbrella sampling calculations, for lipid bilayers composed by only 1,2-dipalmitoyl-sn-glycerol-3-phosphocholine (DPPC), only 1,2-dipalmitoyl-sn-glycerol-3-phosphoserine (DPPS) or a symmetric binary mixture of DPPC and DPPS. In general, the location, the values of minima and maxima of the free energy, and the trend of free energy profiles are influenced by the lipid composition of the lipid bilayer. The driving force in the glyphosate insertion process depends on the lipid composition of the membrane model. If the lipid bilayer is composed solely of DPPS or DPPC, GLYP2- insertion is driven by a favorable enthalpic change. However, if the membrane is composed of a mixture of both lipids, this process is driven by a favorable entropic change. In the lipid bilayer containing DPPS, the glyphosate was found to penetrate hydrated and coordinated with Na+ ions, in contrast to the pure zwitterionic lipid bilayer which penetrated only hydrated. This effect is independent of the concentration of sodium ions present in the bulk solution.

A modifiable, spontaneously formed and biocompatible polymer gel, composed of phosphorylcholine and N-hydroxysuccinimide ester, is reported, which can be subjected to postmodification by amine-cont...

Uncoupling protein 1 (UCP1) is found in the inner mitochondrial membrane of brown adipocytes. In the presence of long-chain fatty acids (LCFAs), UCP1 increases the proton conductance, which, in turn, increases fatty acid oxidation and energy release as heat. Atomic models of UCP1 and UCP2 have been generated based on the NMR backbone structure of UCP2 in dodecylphosphocholine (DPC), a detergent known to inactivate UCP1. Based on NMR titration experiments on UCP1 with LCFA, it has been proposed that K56 and K269 are crucial for LCFA binding and UCP1 activation. Given the numerous controversies on the use of DPC for structure-function analyses of membrane proteins, we revisited those UCP1 mutants in a more physiological context by expressing them in the mitochondria of Saccharomyces cerevisiae. Mitochondrial respiration, assayed on permeabilized spheroplasts, enables the determination of UCP1 activation and inhibition. The K56S, K269S, and K56S/K269S mutants did not display any default in activation, which shows that the NMR titration experiments in DPC detergent are not relevant to UCP1 function.

The effect of branching on the blood circulation and tumor targeting of polymer nanovehicles in vivo was investigated in this study. For the purpose, star-branched poly(lactic acid) and poly(2-methacryloyloxyethyl phosphorylcholine) (PLA-PMPC) copolymers with umbrella-type AB3, (AB3)2, and (AB3)3 architecture were synthesized by branching at the PLA core. Micelles self-assembled from these copolymers were used to evaluate the effect of core branching on blood circulation and tumor targeting The results showed that branching changed the behavior of polymeric self-assembly in solution, thereby changing the size and surface anti-fouling performance of the polymeric micelles. Moreover, star-branched copolymer micelles with a higher branching degree allowed their payload to persist better in blood (half-time prolonged from 7.1, 8.6 to 13.8 h) and for a 1.72-fold higher content at the tumor site. These studies suggest that raising the branching degree of amphiphilic copolymer potentially offers a promising strategy for the design of carriers capable of enhanced circulation and targeting in vivo.

Three-dimensional (3D) representation of a tumor with respect to its size, shape, location, and boundaries is still a challenge in photoacoustic (PA) imaging using artificial contrast agents as probes. We carried out PA imaging of tumors in mice using 800RS-PMPC, which was obtained by coupling of 800RS, a near-infrared cyanine dye, with PMPC, a highly selective tumor-targeting methacrylate polymer having phosphorylcholine side chains, as a probe. The conjugate 800RS-PMPC forms compact nanoparticles (dDLS = 14.3 nm), retains the biocompatibility of the parent polymer (PMPC) and exhibits unprecedented PA performance. When applied to mice bearing a 6 × 3 × 3 mm3 tumor buried 6 mm beneath the skin, the probe 800RS-PMPC selectively accumulates in the tumor and emits PA signals that are strong enough to be unambiguously distinguished from noise signals of endogenous blood/hemoglobin. The PA image thus obtained under high-threshold conditions allows 3D characterization of the tumor in terms of its size, shape, location, and boundaries.

Phosphocholine molecules decorating bacterial cell wall teichoic acids and outer-membrane lipopolysaccharide have fundamental roles in adhesion to host cells, immune evasion, and persistence. Bacteria carrying the operon that performs phosphocholine decoration synthesize phosphocholine after uptake of the choline precursor by LicB, a conserved transporter among divergent species. Streptococcus pneumoniae is a prominent pathogen where phosphocholine decoration plays a fundamental role in virulence. Here, we present cryo–electron microscopy and crystal structures of S. pneumoniae LicB, revealing distinct conformational states and describing architectural and mechanistic elements essential to choline import. Together with in vitro and in vivo functional characterization, we found that LicB displays proton-coupled import activity and promiscuous selectivity involved in adaptation to choline deprivation conditions, and describe LicB inhibition by synthetic nanobodies (sybodies). Our results provide previously unknown insights into the molecular mechanism of a key transporter involved in bacterial pathogenesis and establish a basis for inhibition of the phosphocholine modification pathway across bacterial phyla.

Abs against phosphorylcholine (anti-PC) and Abs against malondialdehyde (anti-MDA) may be protective in chronic inflammation, like atherosclerosis and cardiovascular disease. It is not known how they develop early in life. Ab titers were measured using ELISA in healthy women (n = 105; born into life study) and their children. Plasma samples were collected from the mothers before conception and from the children at birth as well as at 1 and 2 y after birth. Extracted Abs were compared using a proteomics de novo sequencing approach. It was observed that children were born with very low levels of IgM anti-PC, whereas IgM anti-MDA was present at birth. Both IgM anti-PC and anti-MDA increased during the first 2 y of life, but IgM anti-PC in contrast to IgM anti-MDA was still significantly lower than in the mothers. IgG anti-PC decreased after 1 y but reached similar levels as mothers’ after 2 y, whereas IgG anti-MDA reached similar levels as mothers’ already after 1 y. Proteomics peptide sequencing analysis indicated large peptide sequence variation without specific clone expression during the early stage of life compared with the adult stage for which specific peptide sequences dominated. IgM anti-PC levels develop much slower than anti-MDA and are still relatively low at 2 y. We hypothesize that anti-PC is developed by a combination of preprogramming and exposure to the external world, in which infectious agents may play a role. For anti-MDA, preprogramming is likely to play a major role and at an earlier stage than for anti-PC.

Novel biomimetic zwitterionic phosphorylcholine (PC) modified bacterial cellulose (PCBC) membranes were prepared based on the Pudovik reaction of oxidized BC nanofiber clusters and then solution casting technology. Their chemical structure, morphology, hydrophilicity, mechanical and biocompatible properties were characterized and compared with non-modified BC membranes. The composition and morphology analysis of PCBC membranes confirmed the existence of zwitterionic PC groups on the membrane surfaces, and their nano-fibrous structure was kept. Compared with BC membranes, PCBC membranes exhibited better hydrophilicity, similar tensile strength, but decreased rupture strain. And PCBC membranes were non-hemolytic and non-cytotoxic like BC membranes. The anti-biofouling performance investigation revealed that PCBC membranes with zwitterionic surface showed significantly reduced protein adsorption for bovine serum albumin, as well as inhibited cell attachment for both L929 cells and macrophage RAW 264.7. The results strongly suggested that PCBC membranes with excellent cell fouling resistance are expected to be a promising anti-adhesion biomaterial.

This study demonstrates the rapid fabrication and utility of 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer film for cell patterning. The film was obtained on a cell culture surface by microcasting MPC polymer ethanol solution into a degassed polydimethylsiloxane mold with a desired pattern. After removal of the mold, 293AD cells were cultured on the surface of the polymer film with the patterned microstructures. Patterned cell adhesion restricted by the film was successfully maintained during at least a 168-h cultivation. The microcast MPC polymer film can be prepared rapidly and used for efficient long-term cell confinement.

MicroRNAs (miRNAs) play a vital role in many biological processes, including cell growth, differentiation, apoptosis, development, differentiation, and carcinogenesis. Since miRNAs might play a part in cancer initiation and progression, they comprise an original class of promising diagnostic and prognostic molecular markers. In order to systematically understand the regulation of miRNA expression in cancers, the current study analyzed the miRNA expression profile in NCI-60 human cancer cell lines. Over 300 miRNAs exhibited unique expression profiles in cell lines derived from the same lineage. This study identified 9 lineage-specific miRNA expression patterns. Moreover, results indicated that miR-720 and miR-887 are expressed at relatively high levels in breast cancer cell lines compared to other types of cancer. Ultimately, matching NCI-60 drug response data to miR-720 and miR-887 expression profiles revealed that several FDA-approved drugs were inversely related to miR-720 and miR-887. Furthermore, the anti-cancer effect of perifosine was significantly enhanced by inhibiting miR-720 and decreased by miR-720 precursor treatment in breast cancer cell lines. 5-Fu treatment was enhanced by inhibiting miR-887 and decreased by miR-887 precursor treatment. The current results offer insight into the relationship between miRNA expression and their lineage types, and the approach used here represents a potential cancer therapy with the help of miRNAs.

While many approaches to reduce fibrillation of amyloid-β (Aβ) have been aimed at slowing fibril formation, the degradation of fibrils remains challenging. We provide insight into fibril degradation as well as the inhibition of fiber formation by lipid vesicles composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine and 1,2-dioleoyl-sn-glycero-3-phospho-(1'-rac-glycerol). In the presence of vesicles with the optimal lipid composition, fibril formation was inhibited up to 76%. Additionally, by tuning the lipid composition, mature fibril content decreased up to 74% and the β-sheet content of Aβ was significantly reduced. The reduction in fibril and β-sheet content was consistent with a decrease in fibril diameter and could be attributed to the chaperone-like activity of the mixed vesicles. While demonstrating this remarkable activity, our findings present new evidence that lipid composition has a significant effect on the strength of the interaction between lipid bilayers and Aβ peptides/fibrils. This understanding has intriguing therapeutic implications in treating protein misfolding diseases.

The generation of singlet oxygen (1O2) by sonicating a water-soluble complex of fullerene/poly(2-methacryloyloxyethyl phosphorylcholine) (C60/PMPC) was investigated for sonodynamic therapy (SDT). The effect of sonication time and the solubilized concentration of water-soluble fullerene C60 on the amount of generated 1O2 was studied. Singlet oxygen sensor green was used to confirm the generation of 1O2. 1O2 was generated from C60/PMPC under ultrasonic irradiation, and the amount of 1O2 increased with increasing solubilized C60 concentration and irradiation time. In cell viability tests, after 3 h of incubation, the cell viabilities were 10 and 84% in the presence of C60/PMPC with and without sonication, respectively. This result suggests that C60/PMPC shows a sonodynamic effect, which demonstrates its potential application in SDT. The generation of singlet oxygen (1O2) by sonicating a water-soluble complex of fullerene/poly(2-methacryloyloxyethyl phosphorylcholine) (C60/PMPC) was investigated for sonodynamic therapy (SDT). 1O2 was generated from C60/PMPC under ultrasonic irradiation, and the amount of 1O2 increased with increasing solubilized C60 concentration and irradiation time. In cell viability tests, after 3 h of incubation, the cell viabilities were 10% and 84% in the presence of C60/PMPC with and without sonication, respectively. This result suggests that C60/PMPC shows a sonodynamic effect, which demonstrates its potential application in SDT.

Osteoarthritis is a typical degenerative joint disease related to a lubrication deficiency of articular cartilage, which is characterized by increased friction at the joint surface and severe inflammation of the joint capsule. Consequently, therapies combining lubrication restoration and drug intervention are regarded as a promising strategy for the treatment of osteoarthritis. In the present study, thermo-sensitive dual-functional nanospheres, poly[N-isopropylacrylamide-2-methacryloyloxyethyl phosphorylcholine] (PNIPAM-PMPC), are developed through emulsion polymerization. The PNIPAM-PMPC nanospheres could enhance lubrication based on the hydration lubrication mechanism by forming a tenacious hydration layer surrounding the zwitterionic headgroups, and achieve local drug delivery by encapsulating the anti-inflammatory drug diclofenac sodium. The lubrication and drug release tests showed improved lubrication and thermo-sensitive drug release of the nanospheres. The in vitro test using cytokines-treated chondrocytes indicated that the PNIPAM-PMPC nanospheres were biocompatible and upregulated anabolic genes and simultaneously downregulated catabolic genes of the articular cartilage. In summary, the developed PNIPAM-PMPC nanospheres, with the property of enhanced lubrication and local drug delivery, can be an effective nanomedicine for the treatment of osteoarthritis.

The optimum strategy for heart failure (HF) treatment has yet to be elucidated. This study intended to test the benefit of a combination of valsartan (VAL) and perifosine (PER), a specific AKT inhibitor, in protecting against pressure overload induced mouse HF. Mouse were subjected to aortic banding (AB) surgery to establish HF models and then were given vehicle (HF), VAL (50 mg/kg/d), PER (30 mg/kg/d) or combination of VAL and PER for 4 weeks. Mouse with sham surgery treated with VEH were used for control (VEH). VAL or PER treatment could significantly alleviate mouse heart weight, attenuate cardiac fibrosis and improve cardiac function. The combination treatment of VAL and PER presented much better benefit compared with VAL or PER group respectively. PER treatment significantly inhibited AKT/GSK3β/mTORC1 signaling. Besides the classic AT1 inhibition, VAL treatment significantly inhibited MAPK (ERK1/2) signaling. Furthermore, VAL and PER treatment could markedly prevent neonatal rat cardiomyocyte hypertrophy and the activation of neonatal rat cardiac fibroblast. Combination of VAL and PER also presented superior beneficial effects than single treatment of VAL or PER in vitro experiments respectively. This study presented that the combination of valsartan and PER may be a potential treatment for HF prevention.

The surface of human silicone breast implants is covalently grafted at a high density with a 2-methacryloyloxyethyl phosphorylcholine (MPC)-based polymer. Addition of cross-linkers is essential for enhancing the density and mechanical durability of the MPC graft. The MPC graft strongly inhibits not only adsorption but also the conformational deformation of fibrinogen, resulting in the exposure of a buried amino acid sequence, γ377-395, which is recognized by inflammatory cells. Furthermore, the numbers of adhered macrophages and the amounts of released cytokines (MIP-1α, MIP-1β, IL-8, TNFα, IL-1α, IL-1β, and IL-10) are dramatically decreased when the MPC network is introduced at a high density on the silicone surface (cross-linked PMPC-silicone). We insert the MPC-grafted human silicone breast implants into Yorkshire pigs to analyze the in vivo effect of the MPC graft on the capsular formation around the implants. After 6 month implantation, marked reductions of inflammatory cell recruitment, inflammatory-related proteins (TGF-β and myeloperoxidase), a myoblast marker (α-smooth muscle actin), vascularity-related factors (blood vessels and VEGF), and, most importantly, capsular thickness are observed on the cross-linked PMPC-silicone. We propose a mechanism of the MPC grafting effect on fibrous capsular formation around silicone implants on the basis of the in vitro and in vivo results.

Zwitterionic modification can prolong the blood circulation time of nanocarrier in vivo, but zwitterionic content will affect the functions of nanocarrier such as enzyme-responsive and intracellular or extracellular delivery. Therefore, it is necessary to explore the relationship between the zwitterionic content and circulation time of nanocarrier so as to figure out what content of zwitterion can enable the nanocarrier to obtain both the long blood circulation ability and other functions mentioned above. Herein, using nanocapsule as a research model, we investigated the nanocapsule modified with zwitterion of phosphorylcholine (PC) or carboxybetaine (CB) respectively, and through 1H-NMR quantification we determined the zwitterionic surface content, so as to study the effect of PC or CB surface content on blood circulation performance of nanocapsule. In vivo study showed that the nanocapsule possessed an optimal surface filling ratios range for blood circulation of 43–68% for PC and of 20–68% for CB, with the longest t1/2=37.35 h for PC-nanocapsule and t1/2=45.27 h for CB-nanocapsule. Furthermore, the protein adsorption and macrophage endocytosis experiments indicated that when the surface filling ratio reached 43% for PC-nanocapsule and 20% for CB-nanocapsule, it could effectively reduce the protein adsorption and weaken macrophage endocytosis, thus explaining the phenomenon of long circulation time of nanocapsules from the point of protein adsorption and interaction with immune cells. This study proposes a new direction for designing long-circulating nanocarrier, and provides basis for constructing enzyme-responsive and intracellular or extracellular delivery platform.

Proton nuclear spins of dodecyl phosphocholine molecules below the critical micelle concentration are hyperpolarized by using dissolution dynamic nuclear polarization (D-DNP). NMR signal enhancements of 1210±400 and 1610±550 are obtained at 9.4 T, for choline methyls in the head group of the lipid and for the tail-end methyl group, respectively. This polarization is transferred to the unfolded protein through the nuclear Overhauser effect, after dilution to a final denaturant concentration of 0.8 M urea. As a result, the amide and aromatic side-chain signals of the protein are increased up to sixfold. Selective inversion pulses applied either on the head-group or tail-group of the lipid are used to identify the source of the transferred polarization. The normalized cross-relaxation rates of σN,tail =-1.8±0.1 s-1 M-1 and σN,head =-0.5±0.3 s-1 M-1 are obtained, showing a larger polarization transfer from the tail groups. These cross-relaxation rates are determined at a low urea concentration, which constitutes refolding conditions for the protein. The sensitivity enhancement by D-DNP permits to access these conditions with a measurement time on the order of seconds, and may further open the possibility to investigate structural changes in membrane proteins during folding.

We employed two modes of atomic force microscopy to characterize the nanophase-separated structure of a block copolymer thin film from poly(2-methacryloyloxyethyl phosphorylcholine) and poly(3-(met...

The aim of this study was to design a material surface for use in the analysis of the behavior of biomolecules at the interface of direct cell contact. A superhydrophilic surface was prepared with poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), which was grafted onto a substrate with controlled polymer chain density. An arginine-glycine-aspartic acid (RGD) peptide was immobilized at the surface of the polymer graft surface (PMPC-RGD surface). Initial adhesion of the cells to this substrate was observed. The PMPC-RGD surface could enable cell adhesion only through RGD peptide-integrin interactions. The density and movability of the RGD peptide at the terminal of the graft PMPC chain and the orientation of the RGD peptide affected the density of adherent cells. Thus, the PMPC graft surface may be a good candidate for a new platform with the ability to immobilize biomolecules to a defined position and enable accurate analysis of their effects on cells.

C-reactive protein (CRP) can increase up to 1000-fold in blood and form complexes with very low density lipoproteins (VLDL). These complexes are associated with worse outcomes for septic patients, and this suggests a potential pathological role in sepsis. Complex formation is heightened when CRP is over 200 mg/l and levels are associated with the severity of sepsis and blood bacterial culture positivity. Using a mouse bacteremia model, blood bacterial clearance can be delayed by i.v. injection of CRP–VLDL complexes. Complexes are more efficiently taken up by activated U937 cells in vitro and Kupffer cells in vivo than VLDL alone. Both in vitro–generated and naturally occurring CRP–VLDL complexes reduce phagocytosis of bacteria by activated U937 cells. Fcγ and scavenger receptors are involved and a competitive mechanism for clearance of CRP–VLDL complexes and bacteria is demonstrated. Interaction of phosphocholine groups on VLDL with CRP is the major driver for complex formation and phosphocholine can disrupt the complexes to reverse their inhibitory effects on phagocytosis and bacterial clearance. Increased formation of CRP–VLDL complexes is therefore harmful and could be a novel target for therapy in sepsis.

A hydrolysis-resistant polymer bearing new quasi-choline phosphate (quasi-CP) structures as side groups, poly(2-methacryloyloxyethyl choline methylphosphonate) (PMCPm), was designed and synthesized...