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Chondroitin sulfate (CS), a glycosaminoglycan, supports health through various physiological functions, including tissue protection, bone growth, and skin aging prevention. It also contributes to anticoagulant or anti-inflammatory processes, with its primary clinical use being osteoarthritis treatment. This study presents the results of the valorization of lipids and CS, both extracted from salmon co-products through enzymatic processes. The polar lipids, naturally rich in long-chain fatty acids (docosahexaenoic acid DHA C22:6 n-3 and eicosapentaenoic acid EPA C20:5 n-3), and the CS, primarily located in the nasal cartilage, were separated and concentrated before being characterized using various techniques to determine functional and lipid composition. These compounds were then used to formulate liposomes of 63 to 95 nm in size composed of 19.38% of DHA and 7.44% of EPA and encapsulating CS extract with a Δdi-4S/Δdi-6S ratio of 0.53 at 2 weight masses (10–30 kDa and >30 kDa) or CS standard all at two different concentrations. Liposomes were tested on human chondrocytes in inflamed conditions. Thus, compatibility tests, the expression of various inflammation markers at transcriptional and molecular levels, nitrites, and the amount of collagenase produced were analyzed. The results showed that CS, in synergy with the liposomes, played a positive role in combating chondrocyte inflammation even at a low concentration. [ABSTRACT FROM AUTHOR]

To meet the expectations of European consumers, who prioritize agro-environmental factors and local resources, the substitution of fats (palm, coconut, shea) and achieving a balanced fatty acid profile in spreadable fats are gaining more attention. The crystallization at 4 °C of a lipid blend composed of rapeseed oil, anhydrous dairy fats, and emulsifiers was studied using a multi-scale approach (DSC and X-ray diffraction techniques) to understand the emergence of polymorphic structures. Although the addition of PUFA from rapeseed oil reduces the atherogenicity and thrombogenicity indices in the blend, controlling the cooling kinetics influences the shapes (needles and spherulites) and sizes of the crystalline structures (small crystals form at a cooling rate of 1 °C min−1, while larger crystals form at higher rates of 5 and 10 °C min−1). The crystallization behavior revealed differences in polymorphic forms at 4 °C in the blend, with a transition to different forms occurring more rapidly compared to dairy fat (stop-and-return method). The study shows crystalline coexistence (α, β′, and β) in a 2L lamellar structure, with the β′ form being predominant. This structure is ideal for formulating a spreadable product, offering good spreadability (SFC < 32% at 10 °C), mouthfeel, and nutritional benefits compared to butter. [ABSTRACT FROM AUTHOR]

Given the importance of the extracellular medium during tissue formation, it was wise to develop an artificial structure that mimics the extracellular matrix while having improved physico-chemical properties. That is why the choice was focused on gelatin methacryloyl (GelMA), an inexpensive biocompatible hydrogel. Physicochemical and mechanical properties were improved by the incorporation of nanoparticles developed from two innovative fabrication processes: High shear fluid and low frequencies/high frequencies ultrasounds. Both rapeseed nanoliposomes and nanodroplets were successfully incorporated in the GelMA networks during the photo polymerization process. The impact on polymer microstructure was investigated by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and enzymatic degradation investigations. Mechanical stability and viscoelastic tests were conducted to demonstrate the beneficial effect of the functionalization on GelMA hydrogels. Adding nanoparticles to GelMA improved the surface properties (porosity), tuned swelling, and degradability properties. In addition, we observed that nanoemulsion didn't change significantly the mechanical properties to shear and compression solicitations, whereas nanoliposome addition decreased Young's modulus under compression solicitations. Thus, these ways of functionalization allow controlling the design of the material by choosing the type of nanoparticle (nanoliposome or nanoemulsion) in function of the application. [ABSTRACT FROM AUTHOR]

Nanoliposomes are nano-sized vesicles that can be used as drug delivery carriers with the ability to encapsulate both hydrophobic and hydrophilic compounds. Moreover, their lipid compositions facilitate their internalization by cells. However, the interaction between nanoliposomes and the membrane barrier of the human body is not well-known. If cellular tests and animal testing offer a solution, their lack of physiological relevance and ethical concerns make them unsuitable to properly mimic human body complexity. Microfluidics, which allows the environment of the human body to be imitated in a controlled way, can fulfil this role. However, existing models are missing the presence of something that would mimic a basal membrane, often consisting of a simple cell layer on a polymer membrane. In this study, we investigated the diffusion of nanoliposomes in a microfluidic system and found the optimal parameters to maximize their diffusion. Then, we incorporated a custom made GelMA with a controlled degree of substitution and studied the passage of fluorescently labeled nanoliposomes through this barrier. Our results show that highly substituted GelMA was more porous than lower substitution GelMA. Overall, our work lays the foundation for the incorporation of a hydrogel mimicking a basal membrane on a drug delivery microfluidic platform.

There is a growing interest for complex in vitro environments that closely mimic the extracellular matrix and allow cells to grow in microenvironments that are closer to the one in vivo. Protein-based matrices and especially hydrogels can answer this need, thanks to their similarity with the cell microenvironment and their ease of customization. In this study, an experimental design was conducted to study the influence of synthesis parameters on the physical properties of gelatin methacryloyl (GelMA). Temperature, ratio of methacrylic anhydride over gelatin, rate of addition, and stirring speed of the reaction were studied using a Doehlert matrix. Their impact on the following parameters was analyzed: degree of substitution, mass swelling ratio, storage modulus (log(G')), and compression modulus. This study highlights that the most impactful parameter was the ratio of methacrylic anhydride over gelatin. Although, temperature affected the degree of substitution, and methacrylic anhydride addition flow rate impacted the gel's physical properties, namely, its storage modulus and compression modulus. Moreover, this experimental design proposed a theoretical model that described the variation of GelMA's physical characteristics as a function of synthesis conditions.

Curcumin (diferuloylmethane) is a natural bioactive compound with many health-promoting benefits. However, its poor water solubility and bioavailability has limited curcumin&rsquo;s biomedical application. In the present study, we encapsulated curcumin into liposomes, formed from natural sources (salmon lecithin), and characterized its encapsulation efficiency and release profile. The proposed natural carriers increased the solubility and the bioavailability of curcumin. In addition, various physico-chemical properties of the developed soft nanocarriers with and without curcumin were studied. Nanoliposome-encapsulated curcumin increased the viability and network formation in the culture of primary cortical neurons and decreased the rate of apoptosis.

Novel bioactive films were developed from the incorporation of Lactococcus lactis into polysaccharide films. Two different biopolymers were tested: cellulose derivative (hydroxylpropylmethylcellulose (HPMC)) and corn starch. Lactic acid bacteria (LAB) free or previously encapsulated in alginate-pectin composite hydrogel microbeads were added directly to the film forming solution and films were obtained by casting. In order to study the impact of the incorporation of the protective culture into the biopolymer matrix, the water vapour permeability, oxygen permeability, optical and mechanical properties of the dry films were evaluated. Furthermore, the antimicrobial effect of bioactive films against Listeria monocytogenes was studied in synthetic medium. Results showed that the addition of LAB or alginate-pectin microbeads modified slightly films optical properties. In comparison with HPMC films, starch matrix proves to be more sensitive to the addition of bacterial cells or beads. Indeed, mechanical resistance of corn starch films was lower but barrier properties were improved, certainly related to the possible establishment of interactions between alginate-pectin beads and starch. HPMC and starch films containing encapsulated bioactive culture showed a complete inhibition of listerial growth during the first five days of storage at 5 °C and a reduction of 5 logs after 12 days., Competing Interests: The authors declare no conflicts of interest.

Health benefits of unsaturated fatty acids have been demonstrated over the last decades. Nanotechnology provided new process to produce particles such as liposomes and nanoliposomes made of pure phospholipids. These techniques are already used in pharmaceutics to augment the bioavailability and the bioefficiency of drugs. The aim of this paper is to characterize and evaluate the potential of nanoliposomes made of three lecithins (soya, rapeseed and salmon) on cell culture in order to use them in the future as drug delivery systems for tissue engineering. We began to measure, with zetasizer, the radius size of liposomes particles which are 125.5, 136.7 and 130.3 nm respectively for rapeseed, soya and salmon lecithin. Simultaneously, solutions observed by TEM demonstrated the particles were made much of liposomes than droplet (emulsion). Finally, we found that the solutions of lecithins were enough stable over 5 days at 37 °C to be used in culture medium. We investigated the effect of soya, rapeseed and salmon lecithin liposome from 2mg/mL to 5.2 μg/mL on metabolic activity and cell proliferation on rat bone marrow stem cells (rBMSC) during 14 days. The results showed that the three lecithins (soya, rapeseed and salmon) improve cell proliferation at different concentration., (Copyright © 2012 Elsevier B.V. All rights reserved.)