Fucoidan: a promising agent for brain injury and neurodegenerative disease intervention

Therapeutic potential of fucoidan in central nervous system disorders: A systematic review

Central nervous system (CNS) disorders have a complicated pathogenesis, and to date, no single mechanism can fully explain them. Most drugs used for CNS disorders primarily aim to manage symptoms and delay disease progression, and none have demonstrated any pathological reversal. Fucoidan is a safe, sulfated polysaccharide from seaweed that exhibits multiple pharmacological effects, and it is anticipated to be a novel treatment for CNS disorders. To assess the possible clinical uses of fucoidan, this review aims to provide an overview of its neuroprotective mechanism in both in vivo and in vitro CNS disease models, as well as its pharmacokinetics and safety. We included 39 articles on the pharmacology of fucoidan in CNS disorders. In vitro and in vivo experiments demonstrate that fucoidan has important roles in regulating lipid metabolism, enhancing the cholinergic system, maintaining the functional integrity of the blood-brain barrier and mitochondria, inhibiting inflammation, and attenuating oxidative stress and apoptosis, highlighting its potential for CNS disease treatment. Fucoidan has a protective effect against CNS disorders. With ongoing research on fucoidan, it is expected that a natural, highly effective, less toxic, and highly potent fucoidan-based drug or nutritional supplement targeting CNS diseases will be developed.

Fucoidan improving spinal cord injury recovery: Modulating microenvironment and promoting remyelination

INTRODUCTION

Excessive neuroinflammation, apoptosis, glial scar, and demyelination triggered by spinal cord injury (SCI) are major obstacles to SCI repair. Fucoidan, a natural marine plant extract, possesses broad-spectrum anti-inflammatory and immunomodulatory effects and is regarded as a potential therapeutic for various diseases, including neurological disorders. However, its role in SCI has not been investigated.

METHODS

In this study, we established an SCI model in mice and intervened in injury repair by daily intraperitoneal injections of different doses of fucoidan (10 and 20 mg/kg). Concurrently, primary oligodendrocyte precursor cells (OPCs) were treated in vitro to validate the differentiation-promoting effect of fucoidan on OPCs. Basso Mouse Scale (BMS), Louisville Swim Scale (LSS), and Rotarod test were carried out to measure the functional recovery. Immunofluorescence staining, and transmission electron microscopy (TEM) were performed to assess the neuroinflammation, apoptosis, glial scar, and remyelination. Western blot analysis was conducted to clarify the underlying mechanism of remyelination.

RESULTS

Our results indicate that in the SCI model, fucoidan exhibits significant anti-inflammatory effects and promotes the transformation of pro-inflammatory M1-type microglia/macrophages into anti-inflammatory M2-type ones. Fucoidan enhances the survival of neurons and axons in the injury area and improves remyelination. Additionally, fucoidan promotes OPCs differentiation into mature oligodendrocytes by activating the PI3K/AKT/mTOR pathway.

CONCLUSION

Fucoidan improves SCI repair by modulating the microenvironment and promoting remyelination.

Optimization of the Preparation Process of Glucuronomannan Oligosaccharides and Their Effects on the Gut Microbiota in MPTP-Induced PD Model Mice

Parkinson's disease (PD) is a prevalent neurodegenerative disorder, and accumulating evidence suggests a link between dysbiosis of the gut microbiota and the onset and progression of PD. In our previous investigations, we discovered that intraperitoneal administration of glucuronomannan oligosaccharides (GMn) derived from Saccharina japonica exhibited neuroprotective effects in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse model. However, the complicated preparation process, difficulties in isolation, and remarkably low yield have constrained further exploration of GMn. In this study, we optimized the degradation conditions in the preparation process of GMn through orthogonal experiments. Subsequently, an MPTP-induced PD model was established, followed by oral administration of GMn. Through a stepwise optimization, we successfully increased the yield of GMn, separated from crude fucoidan, from 1~2/10,000 to 4~8/1000 and indicated the effects on the amelioration of MPTP-induced motor deficits, preservation of dopamine neurons, and elevation in striatal neurotransmitter levels. Importantly, GMn mitigated gut microbiota dysbiosis induced by MPTP in mice. In particular, GM2 significantly reduced the levels of Akkermansia, Verrucomicrobiota, and Lactobacillus, while promoting the abundance of Roseburia and Prevotella compared to the model group. These findings suggest that GM2 can potentially suppress PD by modulating the gut microbiota, providing a foundation for the development of a novel and effective anti-PD marine drug.

Navigating neurological disorders: harnessing the power of natural compounds for innovative therapeutic breakthroughs

Novel treatments are needed as neurological issues become more frequent worldwide. According to the report, plants, oceans, microorganisms, and animals contain interesting drug discovery compounds. Alzheimer's, Parkinson's, and stroke reviews emphasize neurological disorders' complexity and natural substances' safety. Learn about marine-derived and herbal substances' neuroprotective characteristics and applications. Molecular pathways show these substances' neurological healing effects. This article discusses clinical usage of Bryostatin-1, Fucoidan, Icariin, Salvianolic acid, Curcumin, Resveratrol, etc. Their potential benefits for asthma and Alzheimer's disease are complex. Although limited, the study promotes rigorous scientific research and collaboration between traditional and alternative medical practitioners. Unexplored natural compounds, quality control, well-structured clinical trials, and interdisciplinary collaboration should guide future study. Developing and employing natural chemicals to treat neurological illnesses requires ethical sourcing, sustainability, and public awareness. This detailed analysis covers natural chemicals' current state, challenges, and opportunities in neurological disorder treatment. See also the graphical abstract(Fig. 1).

Surface modification strategies for improved hemocompatibility of polymeric materials: a comprehensive review

Polymeric biomaterials are a widely used class of materials due to their versatile properties. However, as with all other types of materials used for biomaterials, polymers also have to interact with blood. When blood comes into contact with any foreign body, it initiates a cascade which leads to platelet activation and blood coagulation. The implant surface also has to encounter a thromboinflammatory response which makes the implant integrity vulnerable, this leads to blood coagulation on the implant and obstructs it from performing its function. Hence, the surface plays a pivotal role in the design and application of biomaterials. In particular, the surface properties of biomaterials are responsible for biocompatibility with biological systems and hemocompatibility. This review provides a report on recent advances in the field of surface modification approaches for improved hemocompatibility. We focus on the surface properties of polysaccharides, proteins, and synthetic polymers. The blood coagulation cascade has been discussed and blood - material surface interactions have also been explained. The interactions of blood proteins and cells with polymeric material surfaces have been discussed. Moreover, the benefits as well as drawbacks of blood coagulation on the implant surface for wound healing purposes have also been studied. Surface modifications implemented by other researchers to enhance as well as prevent blood coagulation have also been analyzed.

Potential Application of Marine Algae and Their Bioactive Metabolites in Brain Disease Treatment: Pharmacognosy and Pharmacology Insights for Therapeutic Advances

Seaweeds, also known as edible marine algae, are an abundant source of phytosterols, carotenoids, and polysaccharides, among other bioactive substances. Studies conducted in the past few decades have demonstrated that substances derived from seaweed may be able to pass through the blood-brain barrier and act as neuroprotectants. According to preliminary clinical research, seaweed may also help prevent or lessen the symptoms of cerebrovascular illnesses by reducing mental fatigue, preventing endothelial damage to the vascular wall of brain vessels, and regulating internal pressure. They have the ability to control neurotransmitter levels, lessen neuroinflammation, lessen oxidative stress, and prevent the development of amyloid plaques. This review aims to understand the application potential of marine algae and their influence on brain development, highlighting the nutritional value of this "superfood" and providing current knowledge on the molecular mechanisms in the brain associated with their dietary introduction.

Antimetastatic effect of fucoidan against non-small cell lung cancer by suppressing non-receptor tyrosine kinase and extracellular signal-related kinase pathway

BACKGROUND/OBJECTIVES

Fucoidan, a polysaccharide content in brown algae, has been reported to inhibit the growth of cancer cells. The present study aimed to investigate the suppression effects of fucoidan on A549 non-small cell lung cancer cells migration.

MATERIALS/METHODS

The anti-migratory activity of fucoidan in A549 cells was examined by wound healing assay and phalloidin-rhodamine staining in response to fucoidan (0-100 µg/mL) treatment for 48 h. Western blot analysis was performed to clarify the protein expressions relevant to migratory activity.

RESULTS

Fucoidan (25-100 µg/mL) significantly suppressed A549 cells migration together with reduced the intensity of phalloidin-rhodamine which detect filopodia and lamellipodia protrusions at 48 h of treatment. The protein expression indicated that fucoidan significantly suppressed the phosphorylation of focal adhesion kinase (FAK), Src, and extracellular signal-related kinase (ERK). In addition, the phosphorylation of p38 in A549 cells was found to be increased.

CONCLUSIONS

Our data conclude that fucoidan exhibits anti-migratory activities against lung cancer A549 cells mediated by inhibiting ERK1/2 and FAK-Src pathway.

Atrazine Toxicity: The Possible Role of Natural Products for Effective Treatment

There are various herbicides which were used in the agriculture industry. Atrazine (ATZ) is a chlorinated triazine herbicide that consists of a ring structure, known as the triazine ring, along with a chlorine atom and five nitrogen atoms. ATZ is a water-soluble herbicide, which makes it capable of easily infiltrating into majority of the aquatic ecosystems. There are reports of toxic effects of ATZ on different systems of the body but, unfortunately, majority of these scientific reports were documented in animals. The herbicide was reported to enter the body through various routes. The toxicity of the herbicide can cause deleterious effects on the respiratory, reproductive, endocrine, central nervous system, gastrointestinal, and urinary systems of the human body. Alarmingly, few studies in industrial workers showed ATZ exposure leading to cancer. We embarked on the present review to discuss the mechanism of action of ATZ toxicity for which there is no specific antidote or drug. Evidence-based published literature on the effective use of natural products such as lycopene, curcumin, Panax ginseng, Spirulina platensis, Fucoidans, vitamin C, soyabeans, quercetin, L-carnitine, Telfairia occidentalis, vitamin E, Garcinia kola, melatonin, selenium, Isatis indigotica, polyphenols, Acacia nilotica, and Zingiber officinale were discussed in detail. In the absence of any particular allopathic drug, the present review may open the doors for future drug design involving the natural products and their active compounds.

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.

Fucoidan from Fucus vesiculosus prevents the loss of dopaminergic neurons by alleviating mitochondrial dysfunction through targeting ATP5F1a

Parkinson's disease is a neurodegenerative disease that is characterized by the loss of dopaminergic neurons. Fucoidan, which has emerged as a neuroprotective agent, is a marine-origin sulfated polysaccharide enriched in brown algae and sea cucumbers. However, variations in structural characteristics exist among fucoidans derived from different sources, resulting in a wide spectrum of biological effects. It is urgent to find the fucoidan with the strongest neuroprotective effect, and the mechanism needs to be further explored. We isolated and purified four different fucoidan species with different chemical structures and found that Type II fucoidan from Fucus vesiculosus (FvF) significantly improved mitochondrial dysfunction, prevented neuronal apoptosis, reduced dopaminergic neuron loss, and improved motor deficits in an 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse model. Further mechanistic investigation revealed that the ATP5F1a protein is a key target responsible for alleviating mitochondrial dysfunction of FvF to exert neuroprotective effects. This study highlights the favorable properties of FvF for neuroprotection, making FvF a promising candidate for the treatment of PD.

Antioxidant Activity of Fucoidan Modified with Gallic Acid Using the Redox Method

Antioxidant compounds decrease the amount of intracellular reactive oxygen species (ROS) and, consequently, reduce the deleterious effects of ROS in osteoblasts. Here, we modified a 21 kDa fucoidan (FucA) with gallic acid (GA) using the redox method, to potentiate its antioxidant/protective capacity on pre-osteoblast-like cells (MC3T3) against oxidative stress. The 20 kDa FucA-GA contains 37 ± 3.0 mg GA per gram of FucA. FucA-GA was the most efficient antioxidant agent in terms of total antioxidant capacity (2.5 times), reducing power (five times), copper chelation (three times), and superoxide radical scavenging (2 times). Exposure of MC3T3 cells to H2O2 increased ROS levels and activated caspase-3 along with caspase-9. In addition, the cell viability decreased approximately 80%. FucA-GA also provided the most effective protection against oxidative damage caused by H2O2. Treatment with FucA-GA (1.0 mg/mL) increased cell viability (~80%) and decreased intracellular ROS (100%) and caspase activation (~80%). In addition, Fuc-GA (0.1 mg/mL) abolished H2O2-induced oxidative stress in zebra fish embryos. Overall, FucA-GA protected MC3T3 cells from oxidative stress and could represent a possible adjuvant for the treatment of bone fragility by counteracting oxidative phenomena.

Protective effects of fucoidan against kidney diseases: Pharmacological insights and future perspectives

Chronic kidney disease (CKD) is a major public health concern that costs millions of lives worldwide. Natural products are consistently being explored for the development of novel therapeutics in the management of CKD. Fucoidan is a sulfated polysaccharide predominantly extracted from brown seaweed, which has multiple pharmacological benefits against various kidney problems, including chronic renal failure and diabetic nephropathy. This review aimed at exploring literature to update the renoprotective effects of fucoidan, to get an understanding of pharmacological mechanisms, and to highlight the recent progress of fucoidan-based therapeutic development. Evidence shows that fucoidan is effective against inflammation, oxidative stress, and fibrosis in kidney. Fucoidan targets multiple signaling systems, including Nrf2/HO-1, NF-κB, ERK and p38 MAPK, TGF-β1, SIRT1, and GLP-1R signaling that are known to be associated with CKD pathobiology. Despite these pharmacological prospects, the application of fucoidan is limited by its larger molecular size. Notably, low molecular weight fucoidan has shown therapeutic promise in some recent studies. However, future research is warranted to translate the outcome of preclinical studies into clinical use in kidney patients.

Delivery of curcumin by fucoidan-coated mesoporous silica nanoparticles: Fabrication, characterization, and in vitro release performance

Mesoporous silica nanoparticles (MSN) are effective drug delivery carriers because of their adjustable large pore size and high porosity. In this study, complex nanoparticles containing disulfide bonds (SS) were designed and prepared as curcumin (Cur) carriers by using fucoidan (FUC) and MSN as the polymer matrix. The product was characterized using scanning electron microscopy, transmission electron microscopy, dynamic light scattering, Fourier-transform infrared spectroscopy, and an N₂ adsorption and desorption test. When the mass ratio of MSN to FUC was 2:1, the nanospheres particle size was the smallest (295.6 ± 0.98 nm, -35.2 ± 0.8 mV). Furthermore, the curcumin encapsulation rate by MSN-Cur-SS-FUC was over 90%, and the cumulative release rate in 24 h was over 80% due to the combined effect of weak acidity and high glutathione concentration in the tumor site microenvironment. When the Cur concentration was 50 μg/mL, the cell viability of free Cur was 63.8%, the cell viability of MSN-Cur-SS-FUC was 14.5%, and the cell viability of MSN-SS-FUC at the same concentration remained above 74.6%. MSN-SS-FUC composite nanoparticles showed a good delivery of Cur, a lipid-soluble active compound, and provides a new delivery route for other lipid-soluble and poorly bioavailable active compounds.

Esculetin and Fucoidan Attenuate Autophagy and Apoptosis Induced by Zinc Oxide Nanoparticles through Modulating Reactive Astrocyte and Proinflammatory Cytokines in the Rat Brain

We examined the protective effects of esculetin and fucoidan against the neurotoxicity of ZnO NPs in rats. Ninety rats were divided into nine groups and pre-treated with esculetin or fucoidan 1 h before ZnO NP administration on a daily basis for 2 weeks. Serum and brain homogenates were examined by enzyme-linked immunosorbent assay (ELISA), and neurons, microglia, and astrocytes in the hippocampal region were examined with immunohistochemical analysis. The serum levels of interleukin-1-beta (IL-1β), 3-nitrotyrosine (3-NT), superoxide dismutase (SOD), and 8-hydroxy-2′-deoxyguanosine (8-OHdG) were altered in the ZnO NP treatment groups. Brain IL-1β and TNF-α levels were elevated after ZnO NP administration, and these effects were inhibited by esculetin and fucoidan. SOD, 8-OHdG, and acetylcholinesterase (AChE) levels in the brain were decreased after ZnO NP administration. The brain levels of beclin-1 and caspase-3 were elevated after ZnO NP treatment, and these effects were significantly ameliorated by esculetin and fucoidan. The number of reactive astrocytes measured by counting glial fibrillary acidic protein (GFAP)-positive cells, but not microglia, increased following ZnO NP treatment, and esculetin and fucoidan ameliorated the changes. Esculetin and fucoidan may be beneficial for preventing ZnO NP-mediated autophagy and apoptosis by the modulation of reactive astrocyte and proinflammatory cytokines in the rat brain.

Fucoidan as an Autophagy Regulator: Mechanisms and Therapeutic Potentials for Cancer and Other Diseases

Fucoidan, a natural polysaccharide with a variety of classical bioactivities mainly sourced from brown algae, has been extensively studied owing to its favorable pharmacological effects, including anti-inflammatory, anti-tumor, anticoagulant and liver protection. Recently it has been found to play a regulatory role in the processes of autophagy. Autophagy is an important cellular process that effectively protects cells and organisms from stimulating factors such as nutrient deficiency, low cellular ATP levels, metabolic stress, growth factor deprivation and hypoxic conditions. In recent years, many studies have shown that fucoidan can treat human diseases by regulating autophagy process though cell signaling pathways. In this review, we summarize the latest progress in the discovery of natural autophagy regulator of fucoidan for the therapeutic application in cardiac diseases, cancers and liver diseases, aiming to provide the new pharmacological application that fucoidan may treat human diseases by regulating autophagy. Furthermore, we look forward to seeing more diseases that would be treated by autophagy modulator of fucoidan and the discovery of more elaborate autophagy regulation mechanism.