Many marine-derived polysaccharides and their analogues have been reported as showing anticancer and cancer preventive properties. These compounds demonstrate interesting activities and special modes ...of action, differing from each other in both structure and toxicity profile. Herein, literature data concerning anticancer and cancer preventive marine polysaccharides are reviewed. The structural diversity, the biological activities, and the molecular mechanisms of their action are discussed.
Novel radioprotectors are strongly demanded due to their numerous applications in radiobiology and biomedicine, e.g., for facilitating the remedy after cancer radiotherapy. Currently, ...cerium-containing nanomaterials are regarded as promising inorganic radioprotectors due to their unrivaled antioxidant activity based on their ability to mimic the action of natural redox enzymes like catalase and superoxide dismutase and to neutralize reactive oxygen species (ROS), which are by far the main damaging factors of ionizing radiation. The freshwater planarian flatworms are considered a promising system for testing new radioprotectors, due to the high regenerative potential of these species and an excessive amount of proliferating stem cells (neoblasts) in their bodies. Using planarian
, we tested CeO
nanoparticles, well known for their antioxidant activity, along with much less studied CeF
nanoparticles, for their radioprotective potential. In addition, both CeO
and CeF
nanoparticles improve planarian head blastema regeneration after ionizing irradiation by enhancing blastema growth, increasing the number of mitoses and neoblasts' survival, and modulating the expression of genes responsible for the proliferation and differentiation of neoblasts. The CeO
nanoparticles' action stems directly from their redox activity as ROS scavengers, while the CeF
nanoparticles' action is mediated by overexpression of "wound-induced genes" and neoblast- and stem cell-regulating genes.
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► The galactofucans were isolated from brown algae
U. pinnatifida and
S. japonica. ► Sulfated polysaccharides differed in their structural characteristics. ► The galactofucan from
U. ...pinnatifida possessed high antitumor activity in vitro.
During the last decade brown seaweeds attracted much attention as a source of polysaccharides, namely laminarans, alginic acids, and sulfated polysaccharides—fucoidans, with various structures and biological activities.
In this study, sulfated polysaccharides were isolated from brown seaweeds
Saccharina japonica (formerly named Laminaria) and
Undaria pinnatifida and their antitumor activity was tested against human breast cancer T-47D and melanoma SK-MEL-28 cell lines.
The sulfated polysaccharide form
S. japonica was highly branched partially acetylated sulfated galactofucan, built up of (1→3)-α-
l-fucose residues. The sulfated polysaccharide from
U. pinnatifida was partially acetylated highly sulfated galactofucan consisting of (1→3)- or (1→3);(1→4)-α-
l-fucose residues.
Fucoidans from
S. japonica and
U. pinnatifida distinctly inhibited proliferation and colony formation in both breast cancer and melanoma cell lines in a dose-dependent manner. These results indicated that the use of sulfated polysaccharides from brown seaweeds
S. japonica and
U. pinnatifida might be a potential approach for cancer treatment.
Inflammatory bowel disease (IBD) is a serious public health problem worldwide. Current therapeutic strategies that use anti-inflammatory drugs, immunosuppressants, and biological treatments are often ...ineffective and have adverse health effects. In this regard, the use of natural compounds aimed at key pathogenic therapeutic targets in IBD attracts universal attention. Seaweed is a valuable source of structurally diverse biologically active compounds. The materials presented in the review indicate that seaweed extracts and polysaccharides are effective candidates for the development of drugs, biological food additives, and functional nutrition products for the treatment and prevention of IBD. The structural features of algal polysaccharides provide the possibility of exposure to therapeutic targets of IBD, including proinflammatory cytokines, chemokines, adhesion molecules, nuclear factor NF-kB, intestinal epithelial cells, reactive oxygen and nitrogen. Further study of the relationship between the effect of polysaccharides from different types of algae, with different structure and molecular weights on immune and epithelial cells, intestinal microorganisms will contribute to a deeper understanding of their mechanisms and will help in the development of drugs, dietary supplements, functional foods for the treatment of patients with IBD.
With the help of numerical simulation, a detailed analysis of the dynamical effect of the stratospheric quasi-biennial oscillation (QBO) of the equatorial zonal wind on the planetary waves (PWs) up ...to thermospheric heights is carried out for the first time. The 3-dimensional nonlinear mechanistic model of middle and upper atmosphere (MUAM) is used, which is capable of simulating the general atmospheric circulation from the surface up to 300-400 km altitude. The amplitudes of stationary and westward travelling PWs with periods from 4 to 10 days are calculated based on ensembles of model simulations for conditions corresponding to the easterly and westerly QBO phases. Fluxes of wave activity and refractive indices of the atmosphere are calculated to analyze the detailed behavior of the PWs. The important result to emerge is that the stratospheric QBO causes statistically significant changes in the amplitudes of individual wave components up to 25% in the mesosphere-lower thermosphere and 10% changes above 200 km. This change in wave structures should be especially noticeable in the atmosphere during periods of low solar activity, when the direct contribution of solar activity fluctuations is minimized. Propagating from the troposphere to the upper atmosphere, PWs contribute to the propagation of the QBO signal not only from the equatorial region to extratropical latitudes, but also from the stratosphere to the thermosphere. The need for a detailed analysis of large-scale wave disturbances in the upper atmosphere and their relationship with the underlying layers is due, in particular, to their significant impact on satellite navigation and communication systems, which is caused by amplitude and phase fluctuations of the radio signal.
Fucoidans are a class of sulfated fucose-containing bioactive polysaccharides produced by brown algae. The biological effects exhibited by fucoidans are thought to be related to their sulfation. ...However, the lack of methods for sulfation control does not allow for a reliable conclusion about the influence of the position of certain sulfate groups on the observed biological effects. We identified the gene encoding the endo-acting fucoidan sulfatase swf5 in the marine bacterium Wenyingzhuangia fucanilytica CZ1127T. This is the first report on the sequence of fucoidan endo-sulfatase. Sulfatase SWF5 belongs to the subfamily S1_22 of the family S1. SWF5 was shown to remove 4O-sulfation in fucoidans composed from the alternating α-(1→3)- and α-(1→4)-linked residues of sulfated L-fucose but not from fucoidans with the α-(1→3)-linked backbone. The endo-sulfatase was used to selectively prepare 4O-desulfated fucoidan derivatives. It was shown that the 4O-desulfated fucoidans inhibit colony formation of DLD-1 and MCF-7 cells less effectively than unmodified fucoidans. Presumably, 4O-sulfation makes a significant contribution to the anticancer activity of fucoidans.
•Discovered sulfatase SWF5 is a member of S1_22 subfamily of S1 family.•SWF5 cleaved off sulfate groups from the C4 position of α-L-fucose in fucoidans.•SWF5 classified as a sulfated α-(1→3;1→4)-L-fucan endo-4O-sulfatase•4O-Desulfated fucoidan derivatives demonstrate a reduced anticancer effect in vitro.•Reduction of Mw for 4O-desulfated fucoidans leads to a decreased anticancer effect.
The enzymatic depolymerization of fucoidans from brown algae allowed the production of their standardized derivatives with different biological activities. This work aimed to compare the antiviral ...activities of native (FeF) and modified with enzyme (FeHMP) fucoidans from
. The cytotoxicity and antiviral activities of the FeF and FeHMP against herpes viruses (HSV-1, HSV-2), enterovirus (ECHO-1), and human immunodeficiency virus (HIV-1) in Vero and human MT-4 cell lines were examined by methylthiazolyltetrazolium bromide (MTT) and cytopathic effect (CPE) reduction assays, respectively. The efficacy of fucoidans in vivo was evaluated in the outbred mice model of vaginitis caused by HSV-2. We have shown that both FeF and FeHMP significantly inhibited virus-induced CPE in vitro and were more effective against HSV. FeF exhibited antiviral activity against HSV-2 with a selective index (SI) > 40, and FeHMP with SI ˃ 20, when they were added before virus infection or at the early stages of the HSV-2 lifecycle. Furthermore, in vivo studies showed that after intraperitoneal administration (10 mg/kg), both FeF and FeHMP protected mice from lethal intravaginal HSV-2 infection to approximately the same degree (44-56%). Thus, FeF and FeHMP have comparable potency against several DNA and RNA viruses, allowing us to consider the studied fucoidans as promising broad-spectrum antivirals.
•The highly purified fractions of algal laminaran, fucoidan and alginate were isolated.•Seaweed polysaccharides catalyzed the formation of silver nanoparticles.•Alginate possessed the highest ...reduction potential among studied polysaccharides.•The cytotoxicity of nanoparticles varied depending on the properties of polysaccharides.•Silver nanoparticles had antibacterial activity against plant and animal pathogens.
In this report, polysaccharides – alginate, fucoidan, laminaran – were isolated from marine algae Saccharina cichorioides and Fucus evanescens and their activity as a reducing and stabilizing agents in the biogenic synthesis of silver nanoparticles was evaluated. The cytotoxic and antibacterial properties of obtained nanoparticles were also assessed. It was found that all tested polysaccharides could be used as a reducing agent; however, their catalytic activities varied significantly in the following range alginate < fucoidan < laminaran. Nanoparticles demonstrated cytotoxicity against rat C6 glioma cells. It was considerably higher for alginate- and laminaran-obtained nanosilver samples compared to fucoidan. Additionally, silver nanoparticles possessed considerable antibacterial properties more pronounced in fucoidan-obtained samples. Our data demonstrate that different algal polysaccharides can be used for the synthesis of silver nanoparticles with varying bioactivities.
Three different fucoidan fractions were isolated and purified from the brown alga, Sargassum mcclurei. The SmF1 and SmF2 fucoidans are sulfated heteropolysaccharides that contain fucose, galactose, ...mannose, xylose and glucose. The SmF3 fucoidan is highly sulfated (35%) galactofucan, and the main chain of the polysaccharide contains a →3)-α-L-Fucp(2,4SO₃⁻)-(1→3)-α-L-Fucp(2,4SO₃⁻)-(1→ motif with 1,4-linked 3-sulfated α-L-Fucp inserts and 6-linked galactose on reducing end. Possible branching points include the 1,2,6- or 1,3,6-linked galactose and/or 1,3,4-linked fucose residues that could be glycosylated with terminal β-D-Galp residues or chains of alternating sulfated 1,3-linked α-L-Fucp and 1,4-linked β-D-Galp residues, which have been identified in galactofucans for the first time. Both α-L-Fucp and β-D-Galp residues are sulfated at C-2 and/or C-4 (and some C-6 of β-D-Galp) and potentially the C-3 of terminal β-D-Galp, 1,4-linked β-D-Galp and 1,4-linked α-L-Fucp residues. All fucoidans fractions were less cytotoxic and displayed colony formation inhibition in colon cancer DLD-1 cells. Therefore, these fucoidan fractions are potential antitumor agents.
We have studied by means of small angle neutron scattering and diffraction, and molecular dynamics simulations the effect of lipid membrane fluidity on the amyloid-beta peptide interactions with the ...membrane. These interactions have been discovered previously to trigger the reorganization of model membranes between unilamellar vesicles and planar membranes (bicelle-like structures) during the lipid phase transition. The morphology changes were taking place in rigid membranes prepared of fully saturated lipids and were proposed to play a role in the onset of amyloid related disorders. We show in this study that the replacement of fully saturated lipids by more fluid mono-unsaturated lipids eliminates the mentioned morphology changes, most likely due to the absence of phase transition within the temperature range investigated. We have therefore controlled the membrane rigidity also while ensuring the presence of membrane phase transition within the biologically relevant temperatures. It was done by the addition of melatonin and/or cholesterol to the initial membranes made of saturated lipids. Small angle neutron scattering experiments performed over a range of cholesterol and melatonin concentrations show their distinctive effects on the local membrane structure only. The cholesterol for example affects the membrane curvature such that spontaneously formed unilamellar vesicles are of much larger sizes than those formed by the neat lipid membranes or membranes with melatonin added. The temperature dependent experiments, however, reveal no influence on the previously discovered membrane breakage whether cholesterol or melatonin have been added.
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•Amyloid-beta peptides incorporated in a lipid membrane trigger its morphological changes.•The membrane breakage takes place during the lipid phase transition.•Additions of melatonin and cholesterol control the membrane rigidity.•Aβ triggered membrane disruptions remain unaffected by cholesterol and melatonin.
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