Study of fucoidans as natural biomolecules for therapeutical applications in osteoarthritis

DIFUCOSIN: DIclofenac sodium salt loaded FUCOidan-SericIN nanoparticles for the management of chronic inflammatory diseases

The current investigation emphasizes the use of fucoidan and sericin as dual-role biomaterials for obtaining novel nanohybrid systems for the delivery of diclofenac sodium (DS) and the potential treatment of chronic inflammatory diseases. The innovative formulations containing 4 mg/ml of fucoidan and 3 mg/ml of sericin showed an average diameter of about 200 nm, a low polydispersity index (0.17) and a negative surface charge. The hybrid nanosystems demonstrated high stability at various pHs and temperatures, as well as in both saline and glucose solutions. The Rose Bengal assay evidenced that fucoidan is the primary modulator of relative surface hydrophobicity with a two-fold increase of this parameter when compared to sericin nanoparticles. The interaction between the drug and the nanohybrids was confirmed through FT-IR analysis. Moreover, the release profile of DS from the colloidal systems showed a prolonged and constant drug leakage over time both at pH 5 and 7. The DS-loaded nanohybrids (DIFUCOSIN) induced a significant decrease of IL-6 and IL-1β with respect to the active compound in human chondrocytes evidencing a synergistic action of the individual components of nanosystems and the drug and demonstrating the potential application of the proposed nanomedicine for the treatment of inflammation.

Cartilage-inspired self-assembly glycopeptide hydrogels for cartilage regeneration via ROS scavenging

Cartilage injury represents a frequent dilemma in clinical practice owing to its inherently limited self-renewal capacity. Biomimetic strategy-based engineered biomaterial, capable of coordinated regulation for cellular and microenvironmental crosstalk, provides an adequate avenue to boost cartilage regeneration. The level of oxidative stress in microenvironments is verified to be vital for tissue regeneration, yet it is often overlooked in engineered biomaterials for cartilage regeneration. Herein, inspired by natural cartilage architecture, a fibril-network glycopeptide hydrogel (Nap-FFGRGD@FU), composed of marine-derived polysaccharide fucoidan (FU) and naphthalenephenylalanine-phenylalanine-glycine-arginine-glycine-aspartic peptide (Nap-FFGRGD), was presented through a simple supramolecular self-assembly approach. The Nap-FFGRGD@FU hydrogels exhibit a native cartilage-like architecture, characterized by interwoven collagen fibers and attached proteoglycans. Beyond structural simulation, fucoidan-exerted robust biological effects and Arg-Gly-Asp (RGD) sequence-provided cell attachment sites realized functional reinforcement, synergistically promoted extracellular matrix (ECM) production and reactive oxygen species (ROS) elimination, thus contributing to chondrocytes-ECM harmony. In vitro co-culture with glycopeptide hydrogels not only facilitated cartilage ECM anabolic metabolism but also scavenged ROS accumulation in chondrocytes. Mechanistically, the chondro-protective effects induced by glycopeptide hydrogels rely on the activation of endogenous antioxidant pathways associated with nuclear factor erythroid 2-related factor 2 (NRF2). In vivo implantation of glycopeptide hydrogels successfully improved the de novo cartilage generation by 1.65-fold, concomitant with coordinately restructured subchondral bone structure. Collectively, our ingeniously crafted bionic glycopeptide hydrogels simultaneously rewired chondrocytes' function by augmenting anabolic metabolism and rebuilt ECM microenvironment via preserving redox equilibrium, holding great potential for cartilage tissue engineering.

Fucoidan-functionalized gelatin methacryloyl microspheres ameliorate intervertebral disc degeneration by restoring redox and matrix homeostasis of nucleus pulposus

Loss of extracellular matrix (ECM) and dehydration of the nucleus pulposus (NP) are major pathological characteristics of intervertebral disc degeneration (IVDD), the leading cause of low back pain. Excessive reactive oxygen species (ROS) induced by proinflammatory cytokines substantially contribute to IVDD pathogenesis. This study aimed to examine the potential of fucoidan in protecting the matrix metabolism of NP cells and its therapeutic efficacy in the prevention of IVDD. In an inflammatory environment induced by interleukin (IL)-1β, fucoidan treatments demonstrated a dose-dependent enhancement of ECM production in NP cells, while concurrently reducing the expression of matrix degradation enzymes. The protective effect of fucoidan was mediated through the activation of nuclear factor erythroid 2-related factor 2 (NRF2) and subsequent induction of antioxidant enzymes, whereas silencing Nrf2 abrogated the protection of fucoidan on NP cells against IL-1β-induced oxidative stress. Moreover, a novel fucoidan-functionalized gelatin methacryloyl microsphere (Fu@GelMA-MS) was synthesized. The in vivo application of Fu@GelMA-MS via in situ injection in a rat caudal IVD model effectively conserved the ECM components and maintained the hydration of the NP tissue, thereby preventing IVDD caused by puncture. Collectively, fucoidan-functionalized hydrogel microspheres represent a promising strategy for the regeneration of NP and the treatment of IVDD.

Relevance of the Extraction Stage on the Anti-Inflammatory Action of Fucoidans

The anti-inflammatory action of fucoidans is well known, based on both in vitro and some in vivo studies. The other biological properties of these compounds, their lack of toxicity, and the possibility of obtaining them from a widely distributed and renewable source, makes them attractive novel bioactives. However, fucoidans’ heterogeneity and variability in composition, structure, and properties depending on seaweed species, biotic and abiotic factors and processing conditions, especially during extraction and purification stages, make it difficult for standardization. A review of the available technologies, including those based on intensification strategies, and their influence on fucoidan composition, structure, and anti-inflammatory potential of crude extracts and fractions is presented.

A review focusing on the benefits of plant-derived polysaccharides for osteoarthritis

Osteoarthritis (OA) is a chronic joint disease characterized by progressive cartilage degeneration, which imposes a heavy physical and financial burden on the middle-aged and elderly population. As the pathogenesis of OA has not been fully elucidated, it is of great importance to develop targeted therapeutic or preventive medications. Traditional therapeutic drugs, such as non-steroidal anti-inflammatory drugs, steroids and opioids, have significant side effects, making the exploration for safe and effective alternative therapeutic drugs urgent. In recent years, many studies have reported the role of plant-derived polysaccharides in anti-inflammation, anti-oxidation, regulation of chondrocyte metabolism and proliferation, and cartilage protection, and have demonstrated their great potential in the treatment of OA. Therefore, by focusing on studies related to the intervention of plant-derived polysaccharides in OA, including in vivo and in vitro experiments, this review aimed to classify and summarize the existing research findings according to different mechanisms of action. In addition, reports on plant-derived polysaccharides as nanoparticles were also explored. Then, candidate monomers and theoretical bases were provided for the further development and application of novel drugs in the treatment of OA.

In Vitro Study of the Therapeutic Potential of Brown Crude Fucoidans in Osteoarthritis Treatment

Osteoarthritis, one of the most common joint degenerative pathologies, still has no cure, and current treatments, such as nonsteroidal anti-inflammatory drugs, can cause serious adverse effects when taken for a long time. Brown seaweed crude fucoidans are used for the clinical treatment of several pathologies. In this study, the therapeutical potential of these biocompounds was analyzed in primary chondrocytes and the 260TT human chondrocyte cell line. Crude fucoidan from Undaria pinnatifida (Up) and Sargassum muticum (Sm) was obtained by different extraction techniques (microwave-assisted extraction, pressurized hot-water extraction, ultrasound-assisted extraction) and chemically and structurally characterized by Fourier transform infrared spectroscopy, high-performance size-exclusion chromatography, proton nuclear magnetic resonance, and scanning electron microscopy. Once cell viability was confirmed in chondrocytes treated with crude fucoidans, we evaluated their anti-inflammatory effects, observing a significant reduction in IL-6 production stimulated by IL-1β. Findings were confirmed by analysis of IL-6 and IL-8 gene expression, although only fucoidans from Up achieved a statistically significant reduction. Besides this, the antioxidant capacity of crude fucoidans was observed through the upregulation of Nrf-2 levels and the expression of its transcriptional target genes HO-1 and SOD-2, with compounds from Up again showing a more consistent effect. However, no evidence was found that crude fucoidans modulate senescence, as they failed to reduced β-galactosidase activity, cell proliferation, or IL-6 production in chondrocytes stimulated with etoposide. Thus, the findings of this research seem to indicate that the tested crude fucoidans are capable of partially alleviating OA-associated inflammation and oxidative stress, but fail to attenuate chondrocyte senescence.

Comparison of in vitro and in vivo antioxidant activities of commercial fucoidans from Macrocystis pyrifera, Undaria pinnatifida, and Fucus vesiculosus

Antioxidants fucoidans from three seaweeds, Undaria pinnatifida (FUP), Macrocystis pyrifera (FMP) and Fucus vesiculosus (FFV) are sold commercially. However, it is unclear which fucoidan is the most potent antioxidant. Therefore, our objective was to compare the antioxidant activities of these fucoidans. For this purpose, six in vitro antioxidant tests were used, total antioxidant capacity, hydroxyl radical scavenging assay, ferrous and cupric chelating assay, reducing power and H2O2 scavenging assay. The data showed that the fucoidans had a low capacity to donate electrons, and a low capacity to chelate metals. The best activity obtained was in the scavenging of hydroxyl radical. When macrophages were exposed to H2O2 and fucoidans, MTT and live/dead assays showed that all fucoidans protected cells from oxidative damage. The survival rate of zebrafish embryos was significantly higher when exposed to H2O2 and fucoidans than H2O2 alone. In summary, the fucoidans evaluated were ranked according to their antioxidant activity as follows: FMP > FFV > FUP, and the results suggest that these fucoidans, mainly FMP, can be used in the formulation of medicines/foods.

Antifibrotic effect of brown algae-derived fucoidans on osteoarthritic fibroblast-like synoviocytes

Synovial fibrosis is a pathological process which contributes to joint pain and stiffness in several musculoskeletal disorders. Fucoidans, sulfated polysaccharides found in brown algae, have recently emerged as promising therapeutic agents. Despite the increasing amount of evidence suggesting the protective role of fucoidans in different experimental approaches of human fibrotic disorders, the effect of these sulfated polysaccharides on synovial fibrosis has not been investigated yet. By an in vitro experimental approach in fibroblast-like synoviocytes, we detected that fucoidans inhibit their differentiation into myofibroblasts with tumor cell-like characteristics and restore apoptosis. Composition and structure of fucoidan appear to be critical for the detected activity. Furthermore, protective effects of these sulfated polysaccharides are mediated by upregulation of nitric oxide production and modulation of TGF-β/smad pathway. Altogether, our results support the use of fucoidans as therapeutic compounds in the treatment of the fibrotic processes involved in rheumatic pathologies.

In Vitro and In Vivo Dendritic Cell Immune Stimulation Effect of Low Molecular Weight Fucoidan from New Zealand Undaria pinnatifida

Low molecular weight fucoidan (LMWF) has been reported to have immunomodulation effects through the increase of the activation and function of macrophages. In this study, the regulating effect of LMWF from Undaria pinnatifida grown in New Zealand on dendritic cells (DCs) was investigated. We discovered that LMWF could stimulate DCs' maturation and migration, as well as CD4+ and CD8+ T cells' proliferation in vitro. We proved that this immune promoting activity is activated through TLR4 and its downstream MAPK and NF-κB signaling pathways. Further in vivo (mouse model) investigation showed that LMWF has a strong immunological boosting effect, such as facilitating the proliferation of immune cells and increasing the index of immune organs. These findings suggest that LMWF has a positive immunomodulatory effect and is a promising candidate to supplement cancer immunotherapy.

Anti-lung Cancer Marine Compounds: A Review

Lung cancer is one of the most common and lethal cancers in human beings. Lung cancer has been divided into two major types: small cell lung cancer (SCLC) and non-small cell lung carcinoma (NSCLC). Current drugs suffer from various side effects, and the insufficient efficacy of present treatments creates a desire for better more efficient new drugs. This review compares the diversity of marine-derived bioactive compounds from different marine species. Some of the natural products from marine resources are in different stages of clinical trials. By the way, most of them have been studied in vitro and in vivo. Additionally, in this review, the mechanisms of action of marine-derived anti-lung cancer components on lung cancer cell lines have been reviewed. In addition, considering growing rate and the high costs of cancer research, attention must be paid to some aspects of targeting and developing anti-lung cancer drug. In better words, like the other therapeutic strategies that have their particular challenges and weak points, several challenges about marine-derived anti-lung cancer components which exist for scientists for doing research are explained. Moreover, as the attentions in the field of cancer therapy are focused on designing and developing new anticancer strategies for the treatment of cancer in the future, the application of marine-derived anti-lung cancer components in the field of future cancer therapy and their role in future anticancer strategies are briefly discussed.

Prolonged release and shelf-life of anticoagulant sulfated polysaccharides encapsulated with ZIF-8

Natural active polysaccharides are attracting increased attention from pharmaceutical industries for their valuable biological activities. However, the application of polysaccharides has been restricted due to their relatively large molecular weight, complex structure, and instability. Metal-organic frameworks (MOFs) have emerged to help deliver cargo to specific locations, achieving the objectives of eliminating the potential damage to the body, protecting the drugs, and improving therapeutic effectiveness. Here, a pH-responsive zeolitic imidazolate framework (ZIF-8) was synthesized to encapsulated three sulfated polysaccharides (heparin, fucan sulfate, fucosylated chondroitin sulfate) and a non-sulfated polysaccharide, hyaluronic acid. The resulting polysaccharides@ZIF-8 biocomposites showed differences in terms of morphology, particle size, encapsulation, and release efficiency. These biocomposites retained antithrombotic activity and the framework ZIF-8 effectively protected these polysaccharides from degradation and prolonged shelf-life of the anticoagulants from the unfavorable environment.

Fucoidan and Fucoxanthin Attenuate Hepatic Steatosis and Inflammation of NAFLD through Modulation of Leptin/Adiponectin Axis

Non-alcoholic fatty liver disease (NAFLD) is the emerging cause of chronic liver disease globally and lack of approved therapies. Here, we investigated the feasibility of combinatorial effects of low molecular weight fucoidan and high stability fucoxanthin (LMF-HSFx) as a therapeutic approach against NAFLD. We evaluated the inhibitory effects of LMF-HSFx or placebo in 42 NAFLD patients for 24 weeks and related mechanism in high fat diet (HFD) mice model and HepaRG^TM cell line. We found that LMF-HSFx reduces the relative values of alanine aminotransferase, aspartate aminotransferase, total cholesterol, triglyceride, fasting blood glucose and hemoglobin A1c in NAFLD patients. For lipid metabolism, LMF-HSFx reduces the scores of controlled attenuation parameter (CAP) and increases adiponectin and leptin expression. Interestingly, it reduces liver fibrosis in NAFLD patients, either. The proinflammatory cytokines interleukin (IL)-6 and interferon-γ are reduced in LMF-HSFx group. In HFD mice, LMF-HSFx attenuates hepatic lipotoxicity and modulates adipogenesis. Additionally, LMF-HSFx modulates SIRI-PGC-1 pathway in HepaRG cells under palmitic acid-induced lipotoxicity environment. Here, we describe that LMF-HSFx ameliorated hepatic steatosis, inflammation, fibrosis and insulin resistance in NAFLD patients. LMF-HSFx may modulate leptin-adiponectin axis in adipocytes and hepatocytes, then regulate lipid and glycogen metabolism, decrease insulin resistance and is against NAFLD.