Physicochemical data on aqueous polymeric systems of methyl cellulose and lambda- and kappa-carrageenan: SAXS, rheological, densitometry, and sound velocity measurements

Advances in research on malignant transformation of endometriosis-associated ovarian cancer

Endometriosis (EMs) is a prevalent chronic gynecological condition that depends on estrogen, marked by the presence of active endometrial tissue (glands and stroma) outside the uterus. Although pathologically benign, it exhibits biological behaviors such as invasion and metastasis akin to malignant tumors. Endometriosis-associated ovarian carcinoma (EAOC), arising from malignant transformation of EMs, poses significant clinical challenges. However, the mechanisms underlying EAOC pathogenesis remain incompletely understood, with a lack of reliable biomarkers for early diagnosis and personalized treatment strategies. Considering the significant number of EMs patients and the extended period during which malignant transformation can occur, EAOC deserves significant attention. Current research both domestically and internationally indicates that the pathogenesis of EAOC is complex, involving genetic mutations, immune microenvironment, oxidative stress, epigenetic changes, and related areas. This review summarizes the mechanisms underlying the development of EAOC.

Self-assembly at the interface of λ-carrageenan and amphiphilic and cationic peptides: More than meets the eye

Self-assembly of macroscopic membranes at the interface between self-assembling peptides and aqueous polymer solutions of opposite charge has been explored mostly due to the membranes' unique hierarchical structure of three distinct regions, including a layer of perpendicular fibers. We report here on the formation and characterization of self-assembled membranes made with λ-carrageenan and the cationic β-sheet peptides, Pro-Lys-(Phe-Lys)5-Pro (PFK). Using SAXS, SEM, ITC, and rheology, we compared these membranes' morphology and physical properties to membranes made with alginate. We recognized that the polysaccharide's single chain conformation, its solution's viscosity, the potential of hydrogen bonding and electrostatic interactions between the polysaccharides and the peptides charged groups, and the strength of these interactions all affect the properties of the resulting membranes. As a result, we identified that an interplay between the polymer-peptide strength of interactions and the stiffness of the polysaccharide's single chain could be used as a route to control the structure-function relationship of the membranes. These results provide valuable information for creating guidelines to design self-assembly membranes with specific properties.

Swelling of kappa carrageenan hydrogels in simulated body fluid for hypothetical vessel occlusion applications

The swelling ability of kappa-carrageenan (KC) hydrogels was investigated in simulated body fluid (SBF). The SBF mimics the ionic concentrations in the vasa deferentia of human males. The study clarifies if these hydrogels can be adjusted to occlude the vasa deferentia by swelling. For this purpose, swelling to twice the initial volume is desirable. In this study, hydrogels of different primary potassium concentrations, biopolymer concentrations and ethanol-exchanged gels, were immersed in SBF either directly or after drying (pre-dried). We measured the absolute and relative swelling degree, and the swelling rates of the gels. Extensive pre-drying leads to irreversible gel densification and absolute swelling magnitudes decrease. We found that immersion into the SBF also leads to potassium ion accumulation, and network restructuring in the hydrogels. This markedly increases the storage moduli of the gel networks. The ion content in the gel structures also directly affects the swelling speed, the fastest swelling occurred in ethanol-exchanged and pre-dried gels. We found that by pre-drying and potassium content adjustment, swelling of the hydrogels is sufficient to render KC hydrogels as a possible candidate for the occlusion of the vasa deferentia.

Sulfated Polysaccharides from Seaweed Strandings as Renewable Source for Potential Antivirals against Herpes simplex Virus 1

Herpes simplex virus 1 (HSV-1) remains a prominent health concern widespread all over the world. The increasing genital infections by HSV-1 that might facilitate acquisition and transmission of HIV-1, the cumulative evidence that HSV-1 promotes neurodegenerative disorders, and the emergence of drug resistance signify the need for new antiviral agents. In this study, the in vitro anti-herpetic activity of sulfated polysaccharides (SPs) extracted by enzyme or hot water from seaweeds collected in France and Mexico from stranding events, were evaluated. The anti-herpetic activity evaluation of the semi-refined-polysaccharides (sr-SPs) and different ion exchange purified fractions showed a wide range of antiviral activity. Among them, the sr-SPs from the Rhodophyta Halymenia floresii showed stronger activity EC₅₀ 0.68 μg/mL with SI 1470, without cytotoxicity. Further, the antiviral activity of the sr-SPs evaluated at different treatment schemes showed a high EC₅₀ of 0.38 μg/mL during the viral adsorption assays when the polysaccharide and the virus were added simultaneously, whilst the protection on Vero cell during the post-infection assay was effective up to 1 h. The chemical composition, FTIR and ¹H NMR spectroscopic, and molecular weights of the sr-SPs from H. floresii were determined and discussed based on the anti-herpetic activity. The potential utilization of seaweed stranding as a source of antiviral compounds is addressed.

Anti-Herpes simplex virus (HSV-1) activity and antioxidant capacity of carrageenan-rich enzymatic extracts from Solieria filiformis (Gigartinales, Rhodophyta)

Solieria filiformis has been reported to have molecules with various biological activities. In this study we used environmentally friendly extraction methods, such as enzyme-assisted extraction (EAE), as a first step to obtain bioactive compounds from this species. Five combinations of protease (PRO) and carbohydrase (AMG) were utilized (1:0, 0:1, 2:1, 1:1, 1:2 PRO:AMG) to obtain Water Soluble Enzymatic Hydrolysates (WSEHs). Extraction yields, biochemical and structural characterization, as well as in vitro activity against Herpes simplex virus type 1 (HSV-1) and antioxidant capacities were determined. All PRO:AMG combinations significantly improved yields. EAE yielded heterogeneous extracts rich in iota-carrageenan and phenols, as confirmed by FTIR spectra. The highest antiherpetic activity (EC₅₀ 4.5 ± 0.4 μg mL^-1) was found in the WSEHs obtained under 2:1 PRO:AMG. At this combination high antioxidant capacity was also obtained for ABTS (2,2'-Azino-Bis-3-ethylbenzoThiazoline-6-Sulfonic acid) radical scavenging activity and Ferric Reducing Antioxidant Power (FRAP). These could probably play a synergistic role associated to the strong antiviral activity obtained. These results suggest that 2:1 PRO:AMG could be effective in promoting the hydrolytic breakdown of high MW polysaccharides, contributing to the improvement of WSEHs bioactivity. Although Solieria filiformis WSEHs showed promising results, further research, including separation and purification techniques are needed.

Supramolecular structure of methyl cellulose and lambda- and kappa-carrageenan in water: SAXS study using the string-of-beads model

A detailed data analysis utilizing the string-of-beads model was performed on experimental small-angle X-ray scattering (SAXS) curves in a targeted structural study of three, very important, industrial polysaccharides. The results demonstrate the quality of performance for this model on three polymers with quite different thermal structural behavior. Furthermore, they show the advantages of the model used by way of excellent fits in the ranges where the classic approach to the small-angle scattering data interpretation fails and an additional 3D visualization of the model's molecular conformations and anticipated polysaccharide supramolecular structure. The importance of this study is twofold: firstly, the methodology used and, secondly, the structural details of important biopolymers that are widely applicable in practice.