Abnormalities in angiogenesis that are associated with diabetes may contribute to vascular complications and result in disabilities and death. Furthermore, an imbalance in angiogenesis in different ...tissues, including the retina and kidney, can play a role in the pathogenesis of diabetic microvascular complications. Phlorotannins, such as phloroglucinol (PG) and dieckol (DK), which are found in Ecklonia cava exhibit antioxidant and anti-inflammatory activities that improve endothelial function in hypertension. However, reports on the effects of these compounds on diabetes-induced angiogenesis in vivo and in vitro are scarce. In this study, we assessed the antiangiogenic effects of PG and DK on endothelial cells treated with a high concentration of glucose to mimic angiogenesis. In addition, we sought to determine the effects of these compounds on cell proliferation, cell migration, and capillary formation. In silico docking of PG and DK into VEGFR-2 revealed their potential as therapeutic agents against angiogenesis. Further, both compounds were identified to inhibit the formation of the retinal vessel in transgenic zebrafish (flk:EGFP) embryos under high glucose conditions. These findings suggested that PG and DK derived from E. cava are potential inhibitors of angiogenesis in diabetic vascular complications and could, therefore, be used to develop angiogenic agents.
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•PG and DK exert strong affinity for VEGFR-2, thereby blocking the VEGFR-2 pathway.•PG and DK inhibit vital angiogenesis steps in high glucose-induced EA.hy926 cells.•PG and DK regulate retinal vessel diameter in high glucose-induced zebrafish.•PG and DK can be used as nutraceuticals for diabetes-related angiogenesis.
•Sargassum horneri is an edible brown alga with numerous bioactive compounds.•Fucosterol (FST) from S. horneri suppressed mast cell degranulation.•FST downregulated expression of allergy-related ...cytokines/chemokines.•FST mitigated activation of signaling pathways in IgE/BSA-stimulated mast cells.•FST effectively attenuated allergic reactions in BALB/c mice.
Allergic diseases have become a serious problem worldwide and occur when the immune system overreacts to stimuli. Sargassum horneri is an edible marine brown alga with pharmacological relevance in treating various allergy-related conditions. Therefore, this study aimed to investigate the effect of fucosterol (FST) isolated from S. horneri on immunoglobulin E(IgE)/bovine serum albumin (BSA)-stimulated allergic reactions in mouse bone marrow-derived cultured mast cells (BMCMCs) and passive cutaneous anaphylaxis (PCA) in BALB/c mice. The in silico analysis results revealed the binding site modulatory potential of FST on the IgE and IgE-FcεRI complex. The findings of the study revealed that FST significantly suppressed the degranulation of IgE/BSA-stimulated BMCMCs by inhibiting the release of β-hexosaminidase and histamine in a dose-dependent manner. In addition, FST effectively decreased the expression of FcεRI on the surface of BMCMCs and its IgE binding. FST dose-dependently downregulated the expression of allergy-related cytokines (interleukin (IL)-4, -5, -6, -13, tumor necrosis factor (TNF)-α, and a chemokine (thymus and activation-regulated chemokine (TARC)) by suppressing the activation of nuclear factor-κB (NF-κB) and Syk-LAT-ERK-Gab2 signaling in IgE/BSA-stimulated BMCMCs. As per the histological analysis results of the in vivo studies with IgE-mediated PCA in BALB/c mice, FST treatment effectively attenuated the PCA reactions. These findings suggest that FST has an immunopharmacological potential as a naturally available bioactive compound for treating allergic reactions.
Fucoidan has been reported to have various biological activities, such as antioxidant, antitumor and anticoagulant, with various health benefits. However, few studies have been conducted to extract ...fucoidan from Sargassum thunbergii in terms of its immuno-enhancing activities. This aim of this study was to investigate the immuno-enhancing effect of fucoidan (S3) isolated from Sargassum thunbergii through water extraction and ethanol precipitation in RAW 264.7 macrophages and zebrafish. The results showed that S3 contained a relatively high content of fucose and sulfated polysaccharide. Fourier-transform infrared spectroscopy (FTIR) results show that the characteristic peaks at 845 cm−1 and 1220-1270 cm−1 indicate that S3 contains sulfate groups. In vitro, S3 effectively enhanced nitric oxide (NO) production and phagocytic activity. In addition, the results of the study demonstrated that the secretion of tumor necrosis factor-α, interleukin (IL)-6, IL-1β, and IL-10 was upregulated by nuclear factor kappa B (NF-κB) signaling pathway in a dose-dependent manner. In vivo, S3 activates zebrafish immune responses by promoting secretion of NO and activating the NF-κB pathway. Overall, these results suggest that S3 could be used as a functional ingredient added to nutritional supplements and functional foods.
•Fucoidan was obtained by water extraction and ethanol precipitation (S3).•S3 activates the NF-ĸB signaling pathway both in vitro and in vivo.•S3 increases macrophage phagocytosis and the levels of immunomodulatory mediators.
Among the components derived from brown algae, anionic sulfated polysaccharides, which contain sulfated fucose as the major monosaccharide, exert significant biological activities. In this study, we ...purified and structurally characterized sulfated polysaccharides from brown algae, Sargassum binderi (S. binderi; SBPs), and evaluated their biological activity in vitro and in vivo. The SBPs were separated based on their charges and their biophysical properties were investigated according to their functional groups, structural features, and molecular weights using FTIR, NMR, and MALS. Among all the SBPs, Fraction 4 (SBP-F4), with an average molecular weight of 2.867 × 105 g/mol, had the highest polysaccharide and sulfate contents (75.15 ± 0.25% and 24.08 ± 0.18%, respectively). The biological activities of SBP-F4 were investigated further in vitro and in vivo. Our results showed that SBP-F4 significantly suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins in LPS-activated macrophages. Moreover, in the LPS-treated zebrafish model, a significant decrease in cell death and NO production was observed. Collectively, these results show that SBPs not only exert protective effects against LPS-induced cytotoxicity but also inhibit the activation and anti-inflammatory activity of macrophages. Therefore, polysaccharides derived from S. binderi are potential anti-inflammatory agents for use in clinical settings.
Loss of myofibers during muscle atrophy affects functional capacity and quality of life. Dexamethasone, an inducer of rapid atrophy of skeletal myofibers, has been studied as a glucocorticoid ...receptor in muscle atrophy or motor neurodegeneration. In this study, we examined dexamethasone-induced muscle atrophy using zebrafish (
), a vertebrate model, and assessed whether administration of
(maca) as a dietary supplement can prevent muscle atrophy. Changes in skeletal myofibers in zebrafish were evaluated after exposure to dexamethasone for different periods and at different concentrations. Under optimized conditions, zebrafish pre-fed with maca for 3 days were exposed to 0.01% dexamethasone for 1 h/day for 7 days. Thereafter, myofiber loss, damaged muscle contractile proteins, and abnormal exploratory behavior due to the structural and functional impairment of skeletal muscle associated with muscle atrophy were investigated using hematoxylin-eosin, immunofluorescence staining, and behavioral analyses. Our findings suggest that dexamethasone induces muscle atrophy in zebrafish, inhibiting exploratory behavior by inducing myofiber loss, inhibiting muscle contraction, and causing changes in endurance and velocity. Thus, the zebrafish model can be used to screen pharmaceutical agents and to study muscle atrophy. Furthermore, maca is a potential dietary supplement to prevent muscle atrophy, as it protects muscle fibers.
(
) is a well-known brown seaweed widely distributed worldwide. Several biological activities of
have been reported. However, its effects on lipid metabolism and the underlying mechanisms remain ...elusive. In the present study, we examined the inhibitory effect of the active compound "(-)-loliolide ((6S,7aR)-6-hydroxy-4,4,7a-trimethyl-5,6,7,7a-tetrahydro-1-benzofuran-2(4H)-one (HTT))" from
extract on lipid accumulation in differentiated adipocytes. MTT assays demonstrated that (-)-loliolide is not toxic to 3T3-L1 adipocytes in a range of concentrations. (-)-loliolide significantly reduced intracellular lipid accumulation in the differentiated phase of 3T3-L1 adipocytes as shown by Oil Red O staining. Western blot analysis revealed that (-)-loliolide increased the expression of lipolytic protein phospho-hormone-sensitive lipase (p-HSL) and thermogenic protein peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1). Additionally, (-)-loliolide decreased expression of adipogenic and lipogenic proteins, including sterol regulatory element-binding protein-1 (SREBP-1), peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer-binding protein-α (C/EBP-α), and fatty acid-binding protein 4 (FABP4) in 3T3-L1 adipocytes. These results indicate that (-)-loliolide from
could suppress lipid accumulation via regulation of antiadipogenic and prolipolytic mechanisms in 3T3-L1 cells. Considering the multifunctional effect of (-)-loliolide, it can be useful as a lipid-lowering agent in the management of patients who suffer from obesity.
Sargassum species are representative brown algae found worldwide, with 27 species native to the coast of Jeju Island in South Korea. Fucoidans are derived from brown algae and exhibit a variety of ...biological activities. Analysis of the monosaccharide composition is necessary for an in-depth study of fucoidans. However, quantitative analysis of fucoidans with complex structures according to species and habitat is insufficient. Furthermore, complex pre-processing is often required to analyze sugars, making it less economical. This study aimed to validate high-performance liquid chromatography (HPLC)-UV analysis based on 3-methyl-1-phenyl-5-pyrazolone (PMP) derivatization of monosaccharides. The proposed method had a short running time and could be repeated economically using UV detection. The detected PMP-fucose was confirmed to be uninterfered by comparing the analytical chromatograms of the internal standard solution. This analytical method was characterized for system suitability, precision, accuracy, linearity, limit of detection (LOD), and limit of quantification (LOQ), demonstrating satisfactory results. The quantification was verified by comparison with the quantitative results of commercial fucoidan obtained using high-performance anion-exchange chromatography (HPAEC) coupled with pulsed amperometric detection (PAD). Furthermore, the antioxidant effects of algal polysaccharides from Sargassum spp. isolated on Jeju Island was evaluated using a zebrafish model. Polysaccharides from Sargassum coreanum (SCpol) and Sargassum autumnale (SApol) showed remarkable free radical scavenging activities. In addition to the results obtained in the zebrafish experiments, all species-derived polysaccharides showed antioxidant potential. In conclusion, this study demonstrates a useful analytical method using HPLC-UV and PMP derivatives for the effective determination of monosaccharide contents, including fucose, in Sargassum spp.
•An HPLC-UV method has been developed using PMP derivatization of monosaccharides•The method validated for the quantitative analysis of monosaccharides extracted from algae•The method shows satisfactory results for precision, accuracy, LOD, and LOQ.•Excellent antioxidant effects of the polysaccharides from Sargassum species are demonstrated.
Bioactive peptides isolated from edible marine sources have been used as nutraceuticals and functional foods. The present study focuses on the alcalase hydrolysate of
Hippocampus abdominalis
for the ...isolation of antioxidative and angiotensin-I converting enzyme (ACE) inhibitory peptides. Initially, the
H. abdominalis
alcalase hydrolysate (HA) was separated using ultrafiltration (MWCO = 5 kDa), and have obtained the fraction, HA-III (MW ≤ 5 kDa), with strong bioactivity. This was further separated using gel filtration chromatography (Sephadex G-10) and reverse-phase high-performance liquid chromatography (RP-HPLC). The active Sephadex G-10 fraction was analyzed by the Q-TOF mass spectrometry, nine peptides were identified within the molecular mass range between 757.8 and 990.1 Da. Three peptides, GIIGPSGSP, IGTGIPGIW, and QIGFIW, showed strong ACE inhibitory activity and alkyl radical-scavenging activity. Molecular docking studies revealed that the ACE inhibitory activity of the three active peptides is mainly due to hydrogen bonding interactions and active site interactions between active peptides and ACE. This study demonstrated that the active peptides derived from
H. abdominalis
can be isolated and the proteolytic hydrolysates of it are potential antioxidant and antihypertensive agents.
Seaweed-derived compounds are known to possess various biological activities. The present study evaluated the antioxidant potential of (−)-loliolide, a monoterpenoid isolated from
Sargassum horneri
...in Vero cells and zebrafish models. (−)-Loliolide was purified from the chloroform fraction of an
S. horneri
methanol extract using high-performance centrifugal partition chromatography (HPCPC). HPCPC was found to be an effective method to isolate (−)-loliolide, yielding a high purity product. Electron spin resonance evaluation demonstrated that (−)-loliolide had significant alkyl radical scavenging activity (IC
50
: 0.043 ± 0.005 mg mL
−1
). In addition, our study showed that (−)-loliolide demonstrated dose-dependent protective effects for Vero cell viability against 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced intracellular reactive oxygen species (ROS). Moreover, (−)-loliolide reduced lipid peroxidation in AAPH-induced zebrafish embryos, while ameliorating the survival rate and cell death in a dose-dependent manner. These results reveal the antioxidant potential of (−)-loliolide. Future studies highlighting the potential applications of
S. horneri
in manufacturing functional food ingredients are required.
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