Recent Advances in Marine Biomaterials Tailored and Primed for the Treatment of Damaged Soft Tissues

The inherent self-repair abilities of the body often fall short when it comes to addressing injuries in soft tissues like skin, nerves, and cartilage. Tissue engineering and regenerative medicine have concentrated their research efforts on creating natural biomaterials to overcome this intrinsic healing limitation. This comprehensive review delves into the advancement of such biomaterials using substances and components sourced from marine origins. These marine-derived materials offer a sustainable alternative to traditional mammal-derived sources, harnessing their advantageous biological traits including sustainability, scalability, reduced zoonotic disease risks, and fewer religious restrictions. The use of diverse engineering methodologies, ranging from nanoparticle engineering and decellularization to 3D bioprinting and electrospinning, has been employed to fabricate scaffolds based on marine biomaterials. Additionally, this review assesses the most promising aspects in this field while acknowledging existing constraints and outlining necessary future steps for advancement.

Marine collagen-chitosan-fucoidan/chondroitin sulfate cryo-biomaterials loaded with primary human cells envisaging cartilage tissue engineering

Cartilage repair after a trauma or a degenerative disease like osteoarthritis (OA) continues to be a big challenge in current medicine due to the limited self-regenerative capacity of the articular cartilage tissues. To overcome the current limitations, tissue engineering and regenerative medicine (TERM) and adjacent areas have focused their efforts on new therapeutical procedures and materials capable of restoring normal tissue functionalities through polymeric scaffolding and stem cell engineering approaches. For this, the sustainable exploration of marine origin materials has emerged in the last years as a natural alternative to mammal sources, benefiting from their biological properties (e.g., biocompatibility, biodegradability, no toxicity, among others) for the development of several types of scaffolds. In this study, marine collagen(jCOL)-chitosan(sCHT)-fucoidan(aFUC)/chondroitin sulfate(aCS) were cryo-processed (-20 °C, -80 °C, and -196 °C) and a chemical-free crosslinking approach was explored to establish cohesive and stable cryogel materials. The cryogels were intensively characterized to assess their oscillatory behavior, thermal structural stability, thixotropic properties (around 45 % for the best formulations), injectability, and surface structural organization. Additionally, the cryogels demonstrate an interesting microenvironment in in vitro studies using human adipose-derived stem cells (hASCs), supporting their viability and proliferation. In both physic-chemical and in vitro studies, the systems that contain fucoidan in their formulations, i.e., C₁ (jCOL, sCHT, aFUC) and C₃ (jCOL, sCHT, aFUC, aCS), submitted at -80 °C, are those that demonstrated most promising results for future application in articular cartilage tissues.

Analysis of transcriptome expression profiling data in oral leukoplakia and early and late‑stage oral squamous cell carcinoma

The present study screened, potential prognostic biomarkers for oral carcinogenesis. The GSE85195 dataset, which consisted of oral leukoplakia (OL) and early and late-stage oral squamous cell carcinoma (OSCC) samples, was used. The differentially expressed genes (DEGs) in early OSCC vs. OL, late OSCC vs. OL and late OSCC vs. early OSCC groups were screened using the limma package in R. The Short Time-series Expression Miner software package was used to cluster DEGs with similar expression patterns in the course of disease progression (from OL to early and then late-stage OSCC). Moreover, the Database for Annotation, Visualization and Integrated Discovery online analysis tool was used to perform Gene Ontology functional annotation and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis. A protein-protein interaction (PPI) network was also constructed using the Search Tool for the Retrieval of Interacting Genes/Proteins database. Reverse transcription-quantitative PCR was performed to assess the mRNA expression levels of hub node genes in clinical samples, and receiver operating characteristic curve analysis was performed to assess the prognostic value of the hub genes. A total of 4,595, 6,042 and 2,738 DEGs were screened in the early OSCC vs. OL, late OSCC vs. OL and late OSCC vs. early OSCC groups, respectively. A total of 665 overlapping genes were identified when the screened DEGs were compared. Cluster 1 and cluster 7 were identified as the significant clusters, which contained 496 and 341 DEGs, respectively. A PPI network was constructed with 440 interaction pairs. There were five differentially expressed hub nodes identified in different stages from OL to OSCC. The results of the present study indicated that fibronectin 1, signal transducer and activator of transcription 1, collagen type II α1 chain, collagen type X α1 chain and collagen type IV α6 chain might serve as independent diagnostic factors for OL and OSCC, and as prognostic biomarkers for OL carcinogenesis.

Advanced Polymeric Membranes as Biomaterials Based on Marine Sources Envisaging the Regeneration of Human Tissues

The self-repair capacity of human tissue is limited, motivating the arising of tissue engineering (TE) in building temporary scaffolds that envisage the regeneration of human tissues, including articular cartilage. However, despite the large number of preclinical data available, current therapies are not yet capable of fully restoring the entire healthy structure and function on this tissue when significantly damaged. For this reason, new biomaterial approaches are needed, and the present work proposes the development and characterization of innovative polymeric membranes formed by blending marine origin polymers, in a chemical free cross-linking approach, as biomaterials for tissue regeneration. The results confirmed the production of polyelectrolyte complexes molded as membranes, with structural stability resulting from natural intermolecular interactions between the marine biopolymers collagen, chitosan and fucoidan. Furthermore, the polymeric membranes presented adequate swelling ability without compromising cohesiveness (between 300 and 600%), appropriate surface properties, revealing mechanical properties similar to native articular cartilage. From the different formulations studied, the ones performing better were the ones produced with 3 % shark collagen, 3% chitosan and 10% fucoidan, as well as with 5% jellyfish collagen, 3% shark collagen, 3% chitosan and 10% fucoidan. Overall, the novel marine polymeric membranes demonstrated to have promising chemical, and physical properties for tissue engineering approaches, namely as thin biomaterial that can be applied over the damaged articular cartilage aiming its regeneration.

Marine origin biomaterials using a compressive and absorption methodology as cell-laden hydrogel envisaging cartilage tissue engineering

In the recent decade, marine origin products have been growingly studied as building blocks complying with the constant demand of the biomedical sector regarding the development of new devices for Tissue Engineering and Regenerative Medicine (TERM). In this work, several combinations of marine collagen-chitosan-fucoidan hydrogel were formed using a newly developed eco-friendly compressive and absorption methodology to produce hydrogels (CAMPH), which consists of compacting the biopolymers solution while removing the excess of water. The hydrogel formulations were prepared by blending solutions of 5% collagen from jellyfish and/or 3% collagen from blue shark skin, with solutions of 3% chitosan from squid pens and solutions of 10% fucoidan from brown algae, at different ratios. The biopolymer physico-chemical characterization comprised Amino Acid analysis, ATR-FTIR, CD, SDS-PAGE, ICP, XRD, and the results suggested the shark/jellyfish collagen(s) conserved the triple helical structure and had similarities with type I and type II collagen, respectively. The studied collagens also contain a denaturation temperature of around 30-32 °C and a molecular weight between 120 and 125 kDa. Additionally, the hydrogel properties were determined by rheology, water uptake ability, degradation rate, and SEM, and the results showed that all formulations had interesting mechanical (strong viscoelastic character) and structural stability properties, with a significant positive highlight in the formulation of H₃ (blending all biopolymers, i.e., 5% collagen from jellyfish, 3% collagen from skin shark, 3% chitosan and 10% of fucoidan) in the degradation test, that shows a mass loss around 18% over the 30 days, while the H₁ and H₂, present a mass loss of around 35% and 44%, respectively. Additionally, the in vitro cellular assessments using chondrocyte cells (ATDC5) in encapsulated state revealed, for all hydrogel formulations, a non-cytotoxic behavior. Furthermore, Live/Dead assay and Phalloidin/DAPI staining, to assess the cytoskeletal organization, proved that the hydrogels can provide a suitable microenvironment for cell adhesion, viability, and proliferation, after being encapsulated. Overall, the results show that all marine collagen (jellyfish/shark)-chitosan-fucoidan hydrogel formulations provide a good structural architecture and microenvironment, highlighting the H₃ biomaterial due to containing more polymers in their composition, making it suitable for biomedical articular cartilage therapies.

Particulate kidney extracellular matrix: bioactivity and proteomic analysis of a novel scaffold from porcine origin

Decellularized matrices are attractive substrates, being able to retain growth factors and proteins present in the native tissue. Several biomaterials can be produced by processing these matrices. However, new substrates capable of being injected that reverse local kidney injuries are currently scarce. Herein, we hypothesized that the decellularized particulate kidney porcine ECM (pKECM) could support renal progenitor cell cultures for posterior implantation. Briefly, kidneys are cut into pieces, decellularized by immersion on detergent solutions, lyophilized and reduced into particles. Then, ECM particles are analyzed for nuclear material remaining by DNA quantification and histological examination, molecular conformation by FITR and structural morphology by SEM. Protein extraction is also optimized for posterior identification and quantification by mass spectrometry. The results obtained confirm the collagenous structure and composition of the ECM, the effective removal of nucleic material and the preservation of ECM proteins with great similarity to human kidneys. Human renal progenitor cells (hRPCs) are seeded in different ratios with pKECM, on 3D suspensions. The conducted assays for cell viability, proliferation and distribution over 7 days of culture suggest that these matrices as biocompatible and bioactive substrates for hRPCs. Also, by analyzing CD133 expression, an optimal ratio for specific phenotypic expression is revealed, demonstrating the potential of these substrates to modulate cellular behavior. The initial hypothesis of developing and characterizing a particulate ECM biomaterial as a consistent substrate for 3D cultures is successfully validated. The findings in this manuscript suggest these particles as valuable tools for regenerative nephrology by minimizing surgeries and locally reversing small injuries which can lead to chronic renal disfunction.

Multilayer platform to model the bioactivity of hyaluronic acid in gastric cancer

Hyaluronic acid (HA) has a key role in cancer progression. The HA's molecular weight (M_w) is altered in this pathological state: increased concentration of shorter fragments due to the overexpressed hyaluronidases and ROS. Aiming to mimic this microenvironment, we developed a Layer-by-Layer (LbL) platform presenting HA of different M_ws, namely 6.4, 752 and 1500 kDa, to study the influence of HA M_w on the formation of focal adhesion sites (FAs), and the involvement of paxillin and CD44 in this process. High paxillin expression and formation of FAs, via CD44, is observed for MKN45 cells seeded on LbLs presenting HA 6.4 kDa, with the activation of the ERK1/2 pathway, responsible for cell motility and tumour progression. In contrast, activation of p38 pathway, usually related with cancer latency, is observed for cells seeded on LbLs with high M_w HA, i.e. 1500 kDa. Overall, we demonstrate the suitability of the developed platform to study cancer invasiveness.

Marine collagen-chitosan-fucoidan cryogels as cell-laden biocomposites envisaging tissue engineering

The combination of marine origin biopolymers for tissue engineering (TE) applications is of high interest, due to their similarities with the proteins and polysaccharides present in the extracellular matrix of different human tissues. This manuscript reports on innovative collagen-chitosan-fucoidan cryogels formed by the simultaneous blending of these three marine polymers in a chemical-free crosslinking approach. The physicochemical characterization of marine biopolymers comprised FTIR, amino acid analysis, circular dichroism and SDS-PAGE, and suggested that the jellyfish collagen used in the cryogels was not denatured (preserved the triple helical structure) and had similarities with type II collagen. The chitosan presented a high deacetylation degree (90.1%) that can strongly influence the polymer physicochemical properties and biomaterial formation. By its turn, rheology, and SEM studies confirmed that these novel cryogels present interesting properties for TE purposes, such as effective blending of biopolymers without visible material segregation, mechanical stability (strong viscoelastic character), as well as adequate porosity to support cell proliferation and exchange of nutrients and waste products. Additionally, in vitro cellular assessments of all cryogel formulations revealed a non-cytotoxic behavior. The MTS test, live/dead assay and cell morphology assessment (phalloidin DAPI) showed that cryogels can provide a proper microenvironment for cell culturing, supporting cell viability and promoting cell proliferation. Overall, the obtained results suggest that the novel collagen-chitosan-fucoidan cryogels herein presented are promising scaffolds envisaging tissue engineering purposes, as both acellular biomaterials or cell-laden cryogels.

Elastic compliance of fibrillar assemblies in type I collagen

Fibrillary assemblies of Type I collagen find important applications in tissue engineering and as matrices for biophysical studies. The mechanical and structural properties of these structures are governed by factors such as protein concentration, temperature, pH and ionic strength. This study reports on an impedance based analysis of the elastic compliance of fibrillary assemblies of Type I collagen using quartz crystal microbalance with dissipation (QCM-D) at a fundamental frequency of 5 MHz and overtones (n = 3,5,7,9,11). Here, In situ partial fibrillation of the adsorbing collagen followed by its fibrillary assemblies on hydrophilic gold coated quartz surface have been crosslinked using Gallic acid (GA), Chromium (III) gallate (Cr-GA), Catechin (Cat), Tetrakis(hydroxymethyl)phosphonium sulfate (THPS) and Oxazolidine (Ox). This approach allows direct comparison of how viscoelastic properties track the structural evolution of the fiber and network length scales. The collagen crosslinking shows significant positive impact on the protein's mechanical behaviour and on the type of crosslinking agents used. The elastic modulus increases as collagen <GA < THPS < Cr-GA < Cat < Ox. Atomic force microscopic studies on the adsorbed collagen after cross linking confirmed the presence of fibrous assemblies. The results indicate stabilization and reinforcement through strong physical entanglement between the molecules of collagen as well as chemical interaction between collagen matrix and fibrils during cross linking. The elastic compliance evaluated from ΔDissipation/Δfreq. from QCM-D showed that cross linking with GA, Cr-GA and Ox resulted in flexible fibrillary network while agents like THPS and Cat showed elastic moduli similar to that of pure collagen. Results suggest that optimal collagen-crosslinking agent ratio and degree of crosslinking of collagen can help tailor the mechanical properties for specific applications in design of bio-materials of these composites.

Self-assembly of collagen-based biomaterials: preparation, characterizations and biomedical applications

By combining regulatory parameters with characterization methods, researchers can selectively fabricate collagenous biomaterials with various functional responses for biomedical applications.