Dermatan sulfate obtained from the Phallusia nigra marine organism is responsible for antioxidant activity and neuroprotection in the neuroblastoma-2A cell lineage

Recent progress in marine chondroitin sulfate, dermatan sulfate, and chondroitin sulfate/dermatan sulfate hybrid chains as potential functional foods and therapeutic agents

Chondroitin sulfate (CS), dermatan sulfate (DS), and CS/DS hybrid chains are natural complex glycosaminoglycans with high structural diversity and widely distributed in marine organisms, such as fish, shrimp, starfish, and sea cucumber. Numerous CS, DS, and CS/DS hybrid chains with various structures and activities have been obtained from marine animals and have received extensive attention. However, only a few of these hybrid chains have been well-characterized and commercially developed. This review presents information on the extraction, purification, structural characterization, biological activities, potential action mechanisms, and structure-activity relationships of marine CS, DS, and CS/DS hybrid chains. We also discuss the challenges and perspectives in the research of CS, DS, and CS/DS hybrid chains. This review may provide a useful reference for the further investigation, development, and application of CS, DS, and CS/DS hybrid chains in the fields of functional foods and therapeutic agents.

Extraction, Isolation, Characterization, and Biological Activity of Sulfated Polysaccharides Present in Ascidian Viscera Microcosmus exasperatus

Ascidians are marine invertebrates that synthesize sulfated glycosaminoglycans (GAGs) within their viscera. Ascidian GAGs are considered analogues of mammalian GAGs and possess great potential as bioactive compounds, presenting antitumoral and anticoagulant activity. Due to its worldwide occurrence and, therefore, being a suitable organism for large-scale mariculture in many marine environments, our main objectives are to study Microcosmus exasperatus GAGs regarding composition, structure, and biological activity. We also aim to develop efficient protocols for sulfated polysaccharides extraction and purification for large-scale production and clinical applications. GAGs derived from M. exasperatus viscera were extracted by proteolytic digestion, purified by ion-exchange liquid chromatography, and characterized by agarose gel electrophoresis and enzymatic treatments. Anticoagulant activity was evaluated by APTT assays. Antitumoral activity was assessed in an in vitro model of tumor cell culture using MTT, clonogenic, and wound healing assays, respectively. Our results show that M. exasperatus presents three distinct polysaccharides; among them, two were identified: a dermatan sulfate and a fucosylated dermatan sulfate. Antitumoral activity was confirmed for the total polysaccharides (TP). While short-term incubation does not affect tumor cell viability at low concentrations, long-term TP incubation decreases LLC tumor cell growth/proliferation at different concentrations. In addition, TP decreased tumor cell migration at different concentrations. In conclusion, we state that M. exasperatus presents great potential as an alternative GAG source, producing compounds with antitumoral properties at low concentrations that do not possess anticoagulant activity and do not enhance other aspects of malignancy, such as tumor cell migration. Our perspectives are to apply these molecules in future preclinical studies for cancer treatment as antitumoral agents to be combined with current treatments to potentiate therapeutic efficacy.

The effect of the sulfation patterns of dermatan and chondroitin sulfate from vertebrates and ascidians on their neuritogenic and neuroprotective properties

Neurodegeneration is caused by the progressive loss of the structure and function of neurons, leading to cell death, and it is the main cause of many neurodegenerative diseases. Many molecules, such as glycosaminoglycans (GAGs), have been studied for their potential to prevent or treat these diseases. They are widespread in nature and perform an important role in neuritogenesis and neuroprotection. Here we investigated the neuritogenic and neuroprotective role of Phallusia nigra dermatan sulfate (PnD2,6S) and compared it with two distinct structures of chondroitin sulfate (C6S) and dermatan sulfate (D4S). For this study, a neuro 2A murine neuroblastoma cell line was used, and a chemical lesion was induced by the pesticide rotenone (ROT). We observed that PnD2,6S + ROT had a better neuritogenic effect than either C6S + ROT or D4S + ROT at a lower concentration (0.05 μg/mL). When evaluating the mitochondrial membrane potential, PnD2,6S showed a neuroprotective effect at a concentration of 0.4 μg/mL. These data indicate different mechanisms underlying this neuronal potential, in which the sulfation pattern is important for neuritogenic activity, while for neuroprotection all DS/CS structures had similar effects. This finding leads to a better understanding the chemical structures of PnD2,6S, C6S, and D4S and their therapeutic potential.

Recent Progress in Antioxidant Active Substances from Marine Biota

Background: The well-recognized but not fully explored antioxidant activity of marine-biota-derived, biologically active substances has led to interest in their study as substitutes of antibiotics, antiaging agents, anticancer and antiviral drugs, and others. The aim of this review is to present the current state of the art of marine-biota-derived antioxidants to give some ideas for potential industrial applications. Methods: This review is an update for the last 5 years on the marine sources of natural antioxidants, different classes antioxidant compounds, and current derivation biotechnologies. Results: New marine sources of antioxidants, including byproducts and wastes, are presented, along with new antioxidant substances and derivation approaches. Conclusions: The interest in high-value antioxidants from marine biota continues. Natural substances combining antioxidant and antimicrobial action are of particular interest because of the increasing microbial resistance to antibiotic treatments. New antioxidant substances are discovered, along with those extracted from marine biota collected in other locations. Byproducts and wastes provide a valuable source of antioxidant substances. The application of optimized non-conventional derivation approaches is expected to allow the intensification of the production and improvement in the quality of the derived substances. The ability to obtain safe, high-value products is of key importance for potential industrialization.

Natural Polysaccharides as Preventive and Therapeutic Horizon for Neurodegenerative Diseases

Neurodegenerative diseases are a serious and widespread global public health burden amongst aging populations. The total estimated worldwide global cost of dementia was US$818 billion in 2015 and has been projected to rise to 2 trillion US$ by 2030. While advances have been made to understand different neurodegenerative disease mechanisms, effective therapeutic strategies do not generally exist. Several drugs have been proposed in the last two decades for the treatment of different types of neurodegenerative diseases, with little therapeutic benefit, and often with severe adverse and side effects. Thus, the search for novel drugs with higher efficacy and fewer drawbacks is an ongoing challenge in the treatment of neurodegenerative disease. Several natural compounds including polysaccharides have demonstrated neuroprotective and even therapeutic effects. Natural polysaccharides are widely distributed in plants, animals, algae, bacterial and fungal species, and have received considerable attention for their wide-ranging bioactivity, including their antioxidant, anti-neuroinflammatory, anticholinesterase and anti-amyloidogenic effects. In this review, we summarize different mechanisms involved in neurodegenerative diseases and the neuroprotective effects of natural polysaccharides, highlighting their potential role in the prevention and therapy of neurodegenerative disease.

Dermatan sulfate and chondroitin sulfate from Lophius litulon alleviate the allergy sensitized by major royal jelly protein 1

The objective of the present study was to explore the desensitization effect of dermatan sulfate (DS) and chondroitin sulfate (CS) from Lophius litulon (Ll) on mice sensitized by major royal jelly protein 1 (MRJP1). First, the affinity between six glycosaminoglycans and the MRJP1 polyclonal antibody was measured by the ELISA method. Lophius litulon dermatan sulfate (Ll DS) and Lophius litulon chondroitin sulfate (Ll CS) were selected due to their highest binding affinity. Second, the molecular docking method was used to explore the interaction between Ll DS and MRJP1 and Ll CS and MRJP1. The results showed that Ll DS and Ll CS combined with MRJP1 successfully, which meant a potential function of relieving the MRJP1-caused allergy. Finally, the MRJP1-sensitized mice model was established and confirmed that Ll DS and Ll CS had the desensitization ability to relieve MRJP1-induced allergic symptoms. To validate the conclusion, the relief of allergic symptoms in mice was observed. The production of total IgE, MRJP1-specific IgE and histamine was measured. The desensitization mechanism was further studied by measuring cytokines (IL-4 and IFN-γ) from splenocytes stimulated with MRJP1 in vitro. Based on in vivo and in vitro experiments, it was confirmed that Ll DS and Ll CS have the ability to alleviate MRJP1-induced allergic symptoms, which proposes a potential candidate material against IgE-mediated food allergy.

Low-viscosity sodium alginate combined with TiO2 nanoparticles for improving neuroblastoma treatment

Titanium dioxide (TiO₂) nanoparticles have been explored to prevent various cancer developments but it may cause oxidation, inflammation and high cytotoxicity. Alginate has nontoxic, anti-inflammatory, and antioxidant effects. We aimed to explore the effects of alginate-TiO₂ temozolomide (TMZ) nanoparticles on neuroblastoma. A neuroblastoma model was established with neuroblastoma cells and alginate-TiO₂ TMZ nanoparticles were made by spraying low-viscosity sodium alginate (250-360 kDa). The morphology of nanoparticles was observed via scanning electron microscope (SEM). The crystallinity values were analyzed via X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopic study. Neuroblastoma mice were treated with saline solution, TMZ, TiO₂-TMZ and alginate-TiO₂-TMZ nanoparticles. Anti-oxidant, anti-inflammatory, and anti-tumor properties and the mouse survival rates were measured. The spectrometric profiles of alginate-TiO₂ were consistent with those of TiO₂ and alginate. Alginate-TiO₂ TMZ nanoparticles had higher cytotoxicity toward neuroblastoma cells and less inhibitory activity toward normal neuronal cells. The combined nanoparticles increased antioxidant, anti-inflammatory and antitumor activities and prolonged the survival time of the neuroblastoma model (P < 0.05). On the other hand, Alginate-TiO₂ TMZ nanoparticles reduced the levels of mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB). The combined nanoparticles improved neuroblastoma treatment by affecting NF-κB and MAPK signals.