Opportunities and challenges of fucoidan for tumors therapy

Imine Crosslinked, Injectable, and Self-Healing Fucoidan Hydrogel with Immunomodulatory Properties

Biomaterials with inherent anti-inflammatory properties and the ability to foster a pro-regenerative environment hold significant promise for enhancing cell transplantation and tissue regeneration. Fucoidan, a sulfated polysaccharide with well-documented immune-regulatory and antioxidant capabilities, offers strong potential for creating such biomaterials. Yet, there is a lack of engineered fucoidan hydrogels that are injectable and provide tunable physicochemical properties. In this study, the ability of fucoidan to undergo periodate-mediated oxidation is leveraged to introduce aldehydes into backbone (oxidized fucoidan, OFu), enabling the formation of reversible, imine-crosslinks with amine-containing molecules such as gelatin. The imine-crosslinked OFu-gelatin hydrogel provided excellent control over gelation rate and mechanical properties. Counter-intuitively, OFu-gelatin hydrogel exhibited excellent long-term stability (≥28 days), even though imine crosslinks are known to be relatively less stable. Moreover, the OFu-gelatin hydrogels are self-healing, injectable, and biocompatible, supporting cell culture and encapsulation. Furthermore, fucoidan hydrogels displayed immune-modulatory properties both in vitro and in vivo. This innovative injectable fucoidan hydrogel presents a versatile platform for applications in tissue engineering and regenerative medicine.

Marine Natural Products in Inflammation-Related Diseases: Opportunities and Challenges

In recent decades, the potentiality of marine natural products (MNPs) in the medical field has been increasingly recognized. Natural compounds derived from marine microorganisms, algae, and invertebrates have shown significant promise for treating inflammation-related diseases. In this review, we cover the three primary sources of MNPs and their diverse and unique chemical structures and bioactivities. This review aims to summarize the progress of MNPs in combating inflammation-related diseases. Moreover, we cover the functions and mechanisms of MNPs in diseases, highlighting their functions in regulating inflammatory signaling pathways, cellular stress responses, and gut microbiota, among others. Meanwhile, we focus on key technologies and scientific methods to address the current limitations and challenges in MNPs.

Advance of the application of seaweed polysaccharides on antitumor drug delivery systems

In recent years, the morbidity and death rate of patients with tumors have been continuously increasing. How to administer radiotherapy, chemotherapy, and other methods for reducing damage to normal tissue cells and accurately targeting the tumor is one of the key issues in solving the problem of cancer. Using nanocarriers is a feasible approach into targeted control on the release of medicine to increase patient compliance. Nowadays, many researchers are gradually focusing on the application of drug delivery systems with natural ingredients as carriers in tumor therapy. At the same time, natural active ingredients may have better biocompatibility and fewer side effects. Especially, a variety of polysaccharides from algae has exhibited antitumor activity, providing greater possibilities for their use as drug delivery carriers. To facilitate the advancement and clinical translation of algae-derived polysaccharides in medical applications, we summarized the structural features of a range of polysaccharides extracted from macroalgae, their physical properties suitable for use as carriers, and the ways they are utilized in delivering medicines in oncology therapy (particularly in combination with novel oncology therapies, such as immunotherapy and photothermal therapy).

A new promising anticancer agent: A glycosaminoglycan-mimetic derived from the marine bacterial infernan exopolysaccharide

Marine microorganisms are a promising source of innovative compounds for medical applications. The present study aimed to investigate anticancer potential of oversulfated low molecular weight derivatives, named OSIDs, prepared from infernan, a marine bacterial exopolysaccharide. In order to identify a lead, OSIDs with different sulfate contents and molecular weights were firstly evaluated in vitro in a large series of human and murine tumor cell lines. Among all derivatives tested, OSID4 was the most effective, showing a significant dose-dependent inhibitory effect on the viability of cancer cells. OSID4 was then able to significantly slow down progression of lung and melanoma tumor growth in immunocompetent tumor-bearing mouse models. In immunodeficient mice bearing a human lung carcinoma, a notable inhibitory effect of OSID4, comparable to doxorubicin, was observed. In combination with doxorubicin, OSID4 did not exhibit any drug interaction. The activity of OSID4 was confirmed by its modulatory effect on the transcriptomic profile of human lung cancer cells. Finally, toxicity and pharmacokinetic parameters disclosed that OSID4 presented no toxicity and no bleeding risk. In conclusion, by combining its notable anticancer and moderate anticoagulant activities, OSID4 may be promising for treatment of cancers associated with a high risk of thromboembolic events.

Tellurium nanoparticles and Fucoidan-loaded dissolvable microneedles for combined photothermal therapy and anti-angiogenesis in melanoma treatment

Melanoma, an aggressive skin tumor, is prone to metastasis, significantly reducing patient survival rates once it occurs. Tumor microvascularity is a key factor in metastasis, making the inhibition of microvascular formation crucial. Emerging photothermal therapy (PTT) and microneedles (MNs) have garnered attention due to their non-invasive and controllable nature. In this study, we designed dissolvable MNs loaded with bovine serum albumin (BSA)-coated tellurium nanoparticles (Te NPs) and fucoidan for comprehensive melanoma treatment. Poly (2-ethyl-2-oxazoline) (PetOx) and chondroitin sulfate (CS) were employed to fabricate dissolvable MNs. Polycaprolactone (PCL), a non-water-soluble material, was used as the substrate. Te NPs, with their strong photothermal conversion capability, acted as the photothermal agent. Fucoidan, derived from brown algae, possesses anti-tumor and angiogenesis inhibition activities. Upon insertion into the skin, the microneedle tip dissolves in the tissue fluid, releasing Te NPs and fucoidan, while the substrate is removed. Under near-infrared (NIR) laser irradiation, Te NPs achieve PTT, effectively killing tumor cells. Fucoidan inhibits tumor growth by obstructing angiogenesis, thereby cutting off the tumor's nutrient supply. The designed MNs achieved effective tumor suppression through combination therapy with minimal in vivo side effects, providing a safe and effective melanoma treatment.

The Advancements of Marine Natural Products in the Treatment of Alzheimer's Disease: A Study Based on Cell and Animal Experiments

As life expectancy rises and the aging population grows, Alzheimer's disease (AD) has become a significant global health concern. AD is a complex neurodegenerative disorder with an unclear etiology. Current hypotheses primarily focus on β-amyloid (Aβ) aggregation, tau protein hyperphosphorylation, and neuroinflammation as key pathological processes. Given the limited efficacy of existing therapeutic strategies, there is an urgent need to explore novel treatment options. Marine natural products have garnered significant attention due to their unique chemical structures and diverse bioactivities, demonstrating potential for multi-target interventions in AD. This review systematically summarizes the roles of marine-derived compounds, including polysaccharides, carotenoids, and polyphenols, in modulating Aβ aggregation, mitigating tau protein pathology, and regulating gut-brain axis dysfunction. Furthermore, the challenges of current research are discussed, with an emphasis on improving blood-brain barrier permeability and optimizing drug delivery systems to facilitate clinical translation.

Preparation and property study of self-assembled nanoparticles from thiolated fucoidan and doxorubicin

In cancer therapy, addressing the tumor microenvironment remains a critical challenge. This study presented a novel drug delivery system based on thiolated fucoidan (FUC-SH), a marine-derived polysaccharide possessing immunomodulatory properties. FUC-SH was synthesized via cysteine conjugation and self-assembled with doxorubicin (DOX) to form stable nanoparticles through electrostatic interactions and disulfide crosslinking. These nanoparticles exhibited pH/GSH dual-responsive drug release properties, enabling selective drug release in tumor microenvironments. Characterization revealed an average particle size of 141.62 ± 16.94 nm, a Zeta potential of -23.1 ± 2.67 mV, and a high drug-loading efficiency (70.97 ± 1.70 %). Cellular assays demonstrated enhanced tumor-targeted cytotoxicity and immune-stimulating effects, including elevated ROS and cytokine production in RAW 264.7 macrophages. This study focused on in vitro evaluations and the findings highlighted the potential of FUC-SH/DOX nanoparticles as a multifunctional platform for tumor-targeted therapy, while the future studies planned to explore in vivo efficacy.

High mechanical performance and multifunctional degraded fucoidan-derived bioink for 3D bioprinting

While 3D bioprinting serves as a powerful tool in the field of tissue engineering, there is still a lack of natural biomaterial inks that simultaneously combine high mechanical performance with multiple biofunctionalities. Here, a single-component natural bioink with high strength and multi-biofunctionality was developed through the simple degradation and methacrylation of natural fucoidan. Hydrothermal degradation significantly decreased the natural fucoidan solution's viscosity by 99.9 %, meeting the necessary viscosity for Digital Light Processing (DLP) 3D printing. Meanwhile, various biofunctionalities of low molecular weight fucoidan obtained through degradation, such as antimicrobial and antioxidant properties, were developed. The resulting bioink exhibited good mechanical performance (compression modulus of 311 kPa), antimicrobial properties (antibacterial rates of 95.5 % and 97.9 % against E. coli and S. aureus, respectively), and antioxidant properties (intracellular ROS inhibition rates of 94.7 %). Using DLP 3D bioprinting, all printed products showed high shape fidelity with exceptional viability and activity of the encapsulated cells. Due to the unique sulfate structure resembling the natural components of chondroitin sulfate, the in vivo tests revealed its efficacy in promoting cartilage defect repair. In conclusion, the novel bioink blending high mechanical performance with multiple biofunctionalities, shows great potential in the 3D printing of tissue and organ regeneration.

Fucoidan based Ce6-chloroquine self-assembled hydrogel as in situ vaccines to enhance tumor immunotherapy by autophagy inhibition and macrophage polarization

Tumor vaccines have become a promising approach for cancer treatment by triggering antigen-specific responses against tumors. However, autophagy and immunosuppressive tumor microenvironment (TME) reduce antigen exposure and immunogenicity, which limit the effect of tumor vaccines. Here, we develop fucoidan (Fuc) based chlorin e6 (Ce6)-chloroquine (CQ) self-assembly hydrogels (CCFG) as in situ vaccines. Ce6 triggers immune response in situ by photodynamic therapy (PDT) induced immunogenic cell death (ICD) effect, which is further enhanced by macrophage polarization of Fuc and autophagy inhibition of CQ. In vivo studies show that CCFG effectively enhances antigen presentation under laser irradiation, which induces a powerful in situ vaccine effect and significantly inhibits tumor metastasis and recurrence. Our study provides a novel approach for enhancing tumor immunotherapy and inhibiting tumor recurrence and metastasis.

Genomic analysis of Rhodopirellula sp. P2 reveals its role in fucoidan degradation

Fucoidan, the main polysaccharide in various species of brown seaweed, has a high annual production. It is an important source of marine organic carbon and exhibits diverse biological activities and significant application potential. Rhodopirellula sp. P2, a novel marine bacterium of the phylum Planctomycetota, was isolated from intertidal algae samples collected from the Weihai coast, the Yellow Sea, China. The strain P2 is a Gram-negative, aerobic, and pear-shaped bacterium. Here, we report the complete genome sequence of Rhodopirellula sp. P2. The genome of strain P2 consists of a single circular chromosome with 7,291,416 bp and a GC content of 57.38 %, including 5462 protein-coding genes, 2 rRNA genes, and 48 tRNA genes. Genomic analysis revealed that strain P2 possessed 173 CAZymes and 106 sulfatases, indicating that strain P2 has the potential ability to utilize multiple polysaccharides, especially hydrolyze fucoidan to fucose. The genome of strain P2 also encodes a gene cluster related to bacterial microcompartment, suggesting the ability of strain P2 to metabolize fucose. These results enhance the understanding of the diversity and ecological functions of Planctomycetota, and also facilitate the exploitation of Planctomycetota and enzyme resources to utilize fucoidan. This study provides genetic insights into fucoidan catabolism by Planctomycetota, expanding our understanding of fucoidan-degrading microbial groups.

Insight into structural changes in heat-induced whey protein-fucoidan hydrogel by SR-IR and molecular docking techniques

This study aimed to investigate the structural changes in heat-induced polymerized whey protein (PWP)-fucoidan (FCN) hydrogels with different FCN concentration (0 % to 0.75 %, w/v). The interaction of PWP and FCN were traced by simultaneous rheology and Fourier transform infrared spectroscopy spectra (SR-IR) technology. The particle size and absolute zeta potential of PWP-FCN increased significantly (p < 0.05) with higher FCN concentrations, indicating that the formation of PWP-FCN enhanced the stability of the system. The gelation time of PWP-FCN was shortened from 1328 s to 881 s as the FCN concentration increased from 0 to 0.75 % (w/v) paralleled the increased apparent viscosity. The endothermic peak temperature of the hydrogels increased from 95.28 °C to 102.26 °C demonstrating the improved thermal stability due to FCN. The intrinsic fluorescence, surface hydrophobicity, and free thiol groups of PWP-FCN all indicated that FCN could interact with PWP through hydrophobic interactions, which changed the tertiary structure of PWP, and increased the density of PWP-FCN network. Cryogenic scanning electron microscopy (Cryo-SEM) and SEM images showed that the interactions between PWP and FCN resulted to rough and wrinkled microstructure of samples. Results of SR-IR and molecular docking assay both indicated that FCN could also interact with PWP through hydrogen bonds. In summary, FCN could promote the gelation process and the physicochemical properties of PWP-FCN hydrogel. Results of this study could provide theoretical basis for the application of protein-polysaccharide hydrogels in food field.

Extracellular matrix-mimicking cryogels composed of methacrylated fucoidan enhance vascularized skeletal muscle regeneration following volumetric muscle loss

Volumetric muscle loss (VML) significantly impairs the inherent regenerative ability of skeletal muscle and results in chronic functional impairment. Polysaccharides in the muscle extracellular matrix are crucial for regulating cell proliferation and differentiation. Recent studies indicate that fucoidan has beneficial effects on musculoskeletal conditions. However, the impact of fucoidan on skeletal muscle regeneration remains poorly understood. In this study, methacrylated fucoidan (FuMA) was synthesized through chemical grafting of the methacryloyl group onto fucoidan. In vitro experiments demonstrated that treatment with FuMA significantly up-regulated the expression of myogenic markers and promoted the formation of myotubes in C2C12 myoblast cells. Importantly, FuMA treatment led to a significant enhancement in mitochondrial energy metabolism of myoblasts via activation of the NRF2 antioxidant signaling pathway. To further investigate the regenerative properties in repairing skeletal muscle defects, we fabricated a dual crosslinked cryogel consisting of FuMA and methacrylated gelatin (GelMA) with a porous and interconnected structure. In a rat tibialis anterior muscle VML model, implantation of the FuMA/GelMA cryogel effectively promoted the regeneration of muscle fibers, reduced collagen deposition, and facilitated the formation of new blood vessels. Hence, polysaccharide-based cryogels represent a promising implantable biomimetic scaffold for facilitating skeletal muscle regeneration following severe injuries.

Roles and mechanisms of fucoidan against dermatitis: A review

Fucoidan is a sulfate-containing polysaccharide derived from the cell walls of brown algae and marine invertebrates. Fucoidan is widely used for the treatment of various diseases owing to its various biological activities. Dermatitis is an inflammatory reaction that affects the skin. The primary clinical manifestations include atopic dermatitis (AD or eczema) and various subtypes of contact dermatitis. The treatment of dermatitis primarily improves symptoms and reduces inflammation. However, owing to individual variations, some patients have a poor prognosis or symptom recurrence after conventional treatment. Owing to the excellent anti-allergic and anti-inflammatory activities of the low cost nature compound fucoidan, its therapeutic effect in inflammatory diseases has recently attracted the attention of researchers. This article summarizes and analyzes the advantages and pharmacological mechanisms of fucoidan against dermatitis to provide a reference for the selection of drugs for the treatment of dermatitis.

Synergetic approaches of fucoidan and trabectedin complex coated PLGA nanoparticles effectively suppresses proliferation and induce apoptosis for the treatment on non-small cell lung cancer

Traditional methods of treating lung cancer have not been very effective, contributing to the disease's high incidence and death rate. As a result, Fn/Tn-PLGA NPs, a novel directed fucoidan and trabectedin complex loaded PLGA nanoparticle, were produced to investigate the role of developing therapeutic strategies for NSCLC and A549 cell lines. Quantitative real-time polymerase chain reaction was used to examine protein expression and mRNA expression, respectively. Protein activity was knocked down using specific inhibitors and short disrupting RNA transfection. Lastly, cancer cell lines H1299 and A549 were subjected to an in vitro cytotoxicity experiment. Commercial assays were used to assess the levels of cell viability, ROS and proliferation found that Fn/Tn-PLGA NPs effectively killed lung cancer cells. To examine cell death, annexin flow cytometry was employed. In addition, a scratch-wound assay was conducted to assess the migration effects of Fn/Tn-PLGA NPs in a laboratory setting. Finally, PLGA NPs covered with a mix of fucoidan and trabectedin could be a good vehicle for targeting cancerous tissues with chemotherapeutic drugs.

Marine-Derived Anticancer Agents Targeting Apoptotic Pathways: Exploring the Depths for Novel Cancer Therapies

Extensive research has been conducted on the isolation and study of bioactive compounds derived from marine sources. Several natural products have demonstrated potential as inducers of apoptosis and are currently under investigation in clinical trials. These marine-derived compounds selectively interact with extrinsic and intrinsic apoptotic pathways using a variety of molecular mechanisms, resulting in cell shrinkage, chromatin condensation, cytoplasmic blebs, apoptotic bodies, and phagocytosis by adjacent parenchymal cells, neoplastic cells, or macrophages. Numerous marine-derived compounds are currently undergoing rigorous examination for their potential application in cancer therapy. This review examines a total of 21 marine-derived compounds, along with their synthetic derivatives, sourced from marine organisms such as sponges, corals, tunicates, mollusks, ascidians, algae, cyanobacteria, fungi, and actinobacteria. These compounds are currently undergoing preclinical and clinical trials to evaluate their potential as apoptosis inducers for the treatment of different types of cancer. This review further examined the compound's properties and mode of action, preclinical investigations, clinical trial studies on single or combination therapy, and the prospective development of marine-derived anticancer therapies.