Fucoidan isolated from Padina commersonii inhibit LPS-induced inflammation in macrophages blocking TLR/NF-κB signal pathway

Zingerone attenuates concanavalin A-induced acute liver injury by restricting inflammatory responses

Autoimmune hepatitis (AIH), an immune-mediated liver injury, plays an important role in the development and pathogenesis of several liver diseases. However, therapeutic alternatives for the treatment of AIH remain limited. Zingerone (ZIN) is a natural non-toxic phenolic compound extracted from ginger that possesses various pharmacological activities. Thus, this study aimed to investigate the effect of ZIN on AIH using a mouse model of acute liver injury induced by concanavalin A (Con A). To establish liver injury, C57BL/6J mice were intraperitoneally administered ZIN, followed by 20 mg/kg Con A after 3 h. Thereafter, the liver and serum were collected for analysis. The results revealed that ZIN pretreatment significantly suppressed the elevation of liver injury markers induced by Con A exposure and improved the survival of mice. Additionally, ZIN significantly ameliorated liver histopathological injury, hepatocyte apoptosis, and oxidative stress. Notably, ZIN inhibited hepatic M1 macrophage polarization and decreased the expression of M1 macrophage-associated pro-inflammatory genes and cytokines, including interleukin-1β (IL-1β), IL-12, IL-6, and tumor necrosis factor-α (TNF-α). Western blotting analysis indicated that ZIN inhibited the phosphorylation of extracellular receptor kin, c-Jun N-terminal kinase, and p65 in vitro. Taken together, these results suggest that ZIN exerts a protective effect in the Con A-induced acute liver injury model by inhibiting M1 macrophage polarization and suppressing NF-κB, mitogen-activated protein kinase, and interferon regulatory factor signaling pathways. This highlights the possibility of using ZIN as a safe drug for the treatment of liver injury and provides a novel therapeutic direction for clinical studies on liver diseases.

Roles and mechanisms of fucoidan against dermatitis: A review

Fucoidan is a sulfate-containing polysaccharide derived from the cell walls of brown algae and marine invertebrates. Fucoidan is widely used for the treatment of various diseases owing to its various biological activities. Dermatitis is an inflammatory reaction that affects the skin. The primary clinical manifestations include atopic dermatitis (AD or eczema) and various subtypes of contact dermatitis. The treatment of dermatitis primarily improves symptoms and reduces inflammation. However, owing to individual variations, some patients have a poor prognosis or symptom recurrence after conventional treatment. Owing to the excellent anti-allergic and anti-inflammatory activities of the low cost nature compound fucoidan, its therapeutic effect in inflammatory diseases has recently attracted the attention of researchers. This article summarizes and analyzes the advantages and pharmacological mechanisms of fucoidan against dermatitis to provide a reference for the selection of drugs for the treatment of dermatitis.

Stimuli-Mediated Macrophage Switching, Unraveling the Dynamics at the Nanoplatforms-Macrophage Interface

Macrophages play an essential role in immunotherapy and tissue regeneration owing to their remarkable plasticity and diverse functions. Recent bioengineering developments have focused on using external physical stimuli such as electric and magnetic fields, temperature, and compressive stress, among others, on micro/nanostructures to induce macrophage polarization, thereby increasing their therapeutic potential. However, it is difficult to find a concise review of the interaction between physical stimuli, advanced micro/nanostructures, and macrophage polarization. This review examines the present research on physical stimuli-induced macrophage polarization on micro/nanoplatforms, emphasizing the synergistic role of fabricated structure and stimulation for advanced immunotherapy and tissue regeneration. A concise overview of the research advancements investigating the impact of physical stimuli, including electric fields, magnetic fields, compressive forces, fluid shear stress, photothermal stimuli, and multiple stimulations on the polarization of macrophages within complex engineered structures, is provided. The prospective implications of these strategies in regenerative medicine and immunotherapeutic approaches are highlighted. This review will aid in creating stimuli-responsive platforms for immunomodulation and tissue regeneration.

Antipyretic effect of inhaled Tetrastigma hemsleyanum polysaccharide on substance and energy metabolism in yeast-induced pyrexia mice via TLR4/NF-κb signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Tetrastigma hemsleyanum Diels et Gilg, is one of the perennial evergreen plants with grass vine, which has obvious curative effect on severe infectious diseases. Although Tetrastigma hemleyanum has long been recognized for its capacity of antipyretic and antitoxic, its specific mechanism is unknown.

AIM OF THE STUDY

To evaluate the antipyretic effect of Tetrastigma hemleyanum polysaccharide (THP) on mice with dry yeast-induced fever, and to explore its specific antipyretic mechanism.

METHODS

In this study, THP was administered by aerosol in febrile mice. The rectal temperatures of treated animals were monitored at different time points. Histopathological evaluation and various inflammatory indexes were used to assess inflammatory damage. The concentration variations of the central neurotransmitter, endocrine system, substance and energy metabolism indicators were measured to explore the physiological mechanism. Quantitative real-time PCR, Western bolt and Immunohistochemistry were performed to identify the correlation between antipyretic and TLR4/NF-κB signaling pathway.

RESULTS

THP reduced the body temperature of febrile mice induced by dry yeast, as well as the levels of thermogenic cytokines and downregulated the contents of thermoregulatory mediators. THP alleviated the pathological damage of liver and hypothalamus caused by fever. In addition, THP decreased the secretion of thyroid hormone, substance and energy metabolism related indicators. Furthermore, THP significantly suppressed TLR4/NF-κB signaling pathway-related indicators.

CONCLUSIONS

In conclusion, our results suggest that inhaled THP exerts antipyretic effect by mediating the thermoregulatory mediator, decreasing the content of pyrogenic factors to lower the body temperature, and eventually restoring the high metabolic level in the body to normal via inhibiting TLR4/NF-κB signaling pathway. The study provides a reasonable pharmacodynamic basis for the treatment of polysaccharide in febrile-related diseases.

Preparation of Multifunctional Seaweed Polysaccharides Derivatives Composite Hydrogel to Protect Ultraviolet B-Induced Photoaging In Vitro and In Vivo

Seaweed polysaccharides can be used for protective skin photoaging which is caused by long-term exposure to ultraviolet B (UVB). In this study, a multifunctional composite hydrogel (FACP5) is prepared using sulfated galactofucan polysaccharides, alginate oligosaccharides as active ingredients, and polyacrylonitrile modified κ-Carrageenan as substrate. The properties of FACP5 show that it has good water retention, spreadability, and adhesion. The antiphotoaging activity is evaluated in vitro and in vivo. In vitro experiments demonstrate that the components of FACP5 exhibit good biocompatibility, antioxidant, and anti-tyrosinase activities, and could reduce the cell death rate induced by UVB. In vivo experiments demonstrate that, compared with the mice skin in model group, the skin water content treated with FACP5 increases by 29.80%; the thicknesses of epidermis and dermis decrease by 53.56% and 43.98%, respectively; the activities of catalase and superoxide dismutase increase by 1.59 and 0.72 times, respectively; the contents of interleukin-6 and tumor necrosis factor-α decrease by 19.21% and 17.85%, respectively; hydroxyproline content increases by 32.42%; the expression level of matrix metalloproteinase-3 downregulates by 42.80%. These results indicate that FACP5 has skin barrier repairing, antioxidant, anti-inflammatory, and inhibiting collagen degradation activies, FACP5 can be used as a skin protection remedy for photoaging.

Fucoidan's Molecular Targets: A Comprehensive Review of Its Unique and Multiple Targets Accounting for Promising Bioactivities Supported by In Silico Studies

Fucoidan is a class of multifunctional polysaccharides derived from marine organisms. Its unique and diversified physicochemical and chemical properties have qualified them for potential and promising pharmacological uses in human diseases, including inflammation, tumors, immunity disorders, kidney diseases, and diabetes. Physicochemical and chemical properties are the main contributors to these bioactivities. The previous literature has attributed such activities to its ability to target key enzymes and receptors involved in potential disease pathways, either directly or indirectly, where the anionic sulfate ester groups are mainly involved in these interactions. These findings also confirm the advantageous pharmacological uses of sulfated versus non-sulfated polysaccharides. The current review shall highlight the molecular targets of fucoidans, especially enzymes, and the subsequent responses via either the upregulation or downregulation of mediators' expression in various tissue abnormalities. In addition, in silico studies will be applied to support the previous findings and show the significant contributors. The current review may help in understanding the molecular mechanisms of fucoidan. Also, the findings of this review may be utilized in the design of specific oligomers inspired by fucoidan with the purpose of treating life-threatening human diseases effectively.

Protective Effect of Ginsenoside CK against Autoimmune Hepatitis Induced by Concanavalin A

Ginsenoside CK, a kind of rare ginsenoside transformed from protopanaxadiol saponins extracted from the genus Panax, has been proven to possess favorable bioactivities such as anti-inflammatory, anti-cancer, anti-diabetes, and hepatoprotective effects. The current study is targeted to determine the effect of ginsenoside CK on hepatitis induced by concanavalin A (Con A). Mice were treated with different dosages of ginsenoside CK for 7 days, and Con A (15 mg/kg) was intravenously injected to induce autoimmune hepatitis (AIH) after the last administration. The results demonstrated that pretreatment with ginsenoside CK (40 mg/kg) could obviously ameliorate the increase in serum indicators related to liver function such as AST, ALT, and ALP, and hepatic lesions induced by Con A. Meanwhile, ginsenoside CK suppressed hepatocyte apoptosis, which was observed in pathological data, and immunoblotting results showed that the expression of Bax, Bcl-2, and other proteins was regulated by CK. Furthermore, the release of inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and IL-6 in mice with AIH were lowered by the administration of 40 mg/kg of ginsenoside CK. Furthermore, ginsenoside CK elevated the gene expression of Nrf2 and Sirt1 and augmented downstream target genes such as HO-1. In addition, a significant inhibition effect of the TLR4/NF-κB signal was observed in 40 mg/kg CK-pretreated mice compared with the model group. To sum up, the results indicated that ginsenoside CK has a notable hepatoprotective effect against AIH by activating Sirt1/Nrf2 and suppressing the TLR4/NF-κB signaling pathway.

Preparation of a Dual-Functional Sulfated Galactofucan Polysaccharide/Poly(vinyl alcohol) Hydrogel to Promote Macrophage Recruitment and Angiogenic Potential in Diabetic Wound Healing

A diabetic foot ulcer is a common high-risk complication in diabetic patients, but there is still no universal dressing for clinical treatment. In this study, a novel dual-functional sulfated galactofucan polysaccharide/poly(vinyl alcohol) hydrogel (DPH20) is developed during freeze-thaw cycles. Experimental results indicated that DPH20 had a high specific surface area, a dense porous structure, and a good swelling property, which could effectively adsorb the exudates and keep the wound moist. Furthermore, DPH20 exhibited remarkably recruited macrophage capability and accelerated the inflammation stage by improving the expression of the mRNA of CCL2, CCR2, and CCL22 in macrophages. DPH20 could promote cell migration and growth factor release to accelerate tube formation under hyperglycemic conditions in cell models of L929s and HUEVCs, respectively. Significantly, DPH20 accelerates the reconstruction of the full-thickness skin wound by accelerating the recruitment of macrophages, promoting angiogenesis, and releasing the growth factor in the diabetic mouse model. Collectively, DPH20 is a promising multifunctional dressing to reshape the damaged tissue environment and accelerate wound healing. This study provides an efficient strategy to repair and regenerate diabetic skin ulcers.

The Anti-Inflammatory Effect of Low Molecular Weight Fucoidan from Sargassum siliquastrum in Lipopolysaccharide-Stimulated RAW 264.7 Macrophages via Inhibiting NF-κB/MAPK Signaling Pathways

Brown seaweed is a rich source of fucoidan, which exhibits a variety of biological activities. The present study discloses the protective effect of low molecular weight fucoidan (FSSQ) isolated from an edible brown alga, Sargassum siliquastrum, on lipopolysaccharide (LPS)-stimulated inflammatory responses in RAW 264.7 macrophages. The findings of the study revealed that FSSQ increases cell viability while decreasing intracellular reactive oxygen species production in LPS-stimulated RAW 264.7 macrophages dose-dependently. FSSQ reduced the iNOS and COX-2 expression, inhibiting the NO and prostaglandin E2 production. Furthermore, mRNA expression of IL-1β, IL-6, and TNF-α was downregulated by FSSQ via modulating MAPK and NF-κB signaling. The NLRP3 inflammasome protein complex, including NLRP3, ASC, and caspase-1, as well as the subsequent release of pro-inflammatory cytokines, such as IL-1β and IL-18, release in LPS-stimulated RAW 264.7 macrophages was inhibited by FSSQ. The cytoprotective effect of FSSQ is indicated via Nrf2/HO-1 signaling activation, which is considerably reduced upon suppression of HO-1 activity by ZnPP. Collectively, the study revealed the therapeutic potential of FSSQ against inflammatory responses in LPS-stimulated RAW 264.7 macrophages. Moreover, the study suggests further investigations on commercially viable methods for fucoidan isolation.

Impact of Enzymatically Extracted High Molecular Weight Fucoidan on Lipopolysaccharide-Induced Endothelial Activation and Leukocyte Adhesion

The endothelial cell lining creates an interface between circulating blood and adjoining tissue and forms one of the most critical barriers and targets for therapeutical intervention. Recent studies suggest that fucoidans, sulfated and fucose-rich polysaccharides from brown seaweed, show multiple promising biological effects, including anti-inflammatory properties. However, their biological activity is determined by chemical characteristics such as molecular weight, sulfation degree, and molecular structure, which vary depending on the source, species, and harvesting and isolation method. In this study, we investigated the impact of high molecular weight (HMW) fucoidan extract on endothelial cell activation and interaction with primary monocytes (MNCs) in lipopolysaccharide (LPS)-induced inflammation. Gentle enzyme-assisted extraction combined with fractionation by ion exchange chromatography resulted in well-defined and pure fucoidan fractions. FE_F3, with a molecular weight ranging from 110 to 800 kDa and a sulfate content of 39%, was chosen for further investigation of its anti-inflammatory potential. We observed that along with higher purity of fucoidan fractions, the inflammatory response in endothelial mono- and co-cultures with MNCs was reduced in a dose-dependent manner when testing two different concentrations. This was demonstrated by a decrease in IL-6 and ICAM-1 on gene and protein levels and a reduced gene expression of TLR-4, GSK3β and NF-kB. Expression of selectins and, consequently, the adhesion of monocytes to the endothelial monolayer was reduced after fucoidan treatment. These data indicate that the anti-inflammatory effect of fucoidans increases with their purity and suggest that fucoidans might be useful in limiting the inflammatory response of endothelial cells in cases of LPS-induced bacterial infection.

Comparison of Fucoidans from Saccharina latissima Regarding Age-Related Macular Degeneration Relevant Pathomechanisms in Retinal Pigment Epithelium

Fucoidans from brown algae are described as anti-inflammatory, antioxidative, and antiangiogenic. We tested two Saccharina latissima fucoidans (SL-FRO and SL-NOR) regarding their potential biological effects against age-related macular degeneration (AMD). Primary porcine retinal pigment epithelium (RPE), human RPE cell line ARPE-19, and human uveal melanoma cell line OMM-1 were used. Cell survival was assessed in tetrazolium assay (MTT). Oxidative stress assays were induced with erastin or H2O2. Supernatants were harvested to assess secreted vascular endothelial growth factor A (VEGF-A) in ELISA. Barrier function was assessed by measurement of trans-epithelial electrical resistance (TEER). Protectin (CD59) and retinal pigment epithelium-specific 65 kDa protein (RPE65) were evaluated in western blot. Polymorphonuclear elastase and complement inhibition assays were performed. Phagocytosis of photoreceptor outer segments was tested in a fluorescence assay. Secretion and expression of proinflammatory cytokines were assessed with ELISA and real-time PCR. Fucoidans were chemically analyzed. Neither toxic nor antioxidative effects were detected in ARPE-19 or OMM-1. Interleukin 8 gene expression was slightly reduced by SL-NOR but induced by SL-FRO in RPE. VEGF secretion was reduced in ARPE-19 by SL-FRO and in RPE by both fucoidans. Polyinosinic:polycytidylic acid induced interleukin 6 and interleukin 8 secretion was reduced by both fucoidans in RPE. CD59 expression was positively influenced by fucoidans, and they exhibited a complement and elastase inhibitory effect in cell-free assay. RPE65 expression was reduced by SL-NOR in RPE. Barrier function of RPE was transiently reduced. Phagocytosis ability was slightly reduced by both fucoidans in primary RPE but not in ARPE-19. Fucoidans from Saccharina latissima, especially SL-FRO, are promising agents against AMD, as they reduce angiogenic cytokines and show anti-inflammatory and complement inhibiting properties; however, potential effects on gene expression and RPE functions need to be considered for further research.

Anti-inflammatory properties of antiangiogenic fucoidan in retinal pigment epithelium cells

Age-related macular degeneration (AMD) is a multifactorial disease in which angiogenesis, oxidative stress and inflammation are important contributing factors. In this study, we investigated the anti-inflammatory effects of a fucoidan from the brown algae Fucus vesiculosus (FV) in primary porcine RPE cells. Inflammation was induced by lipopolysaccharide (LPS), polyinosinic:polycytidylic acid (Poly I:C), Pam2CSK4 (Pam), or tumor necrosis factor alpha (TNF-α). Cell viability was tested with thiazolyl blue tetrazolium bromide (MTT) test, barrier function by measuring transepithelial electric resistance (TEER), interleukin 6 (IL-6) and interleukin 8 (IL-8) secretion in ELISA, retinal pigment epithelium-specific 65 kDa protein (RPE65) and protectin (CD59) expression in Western blot, gene expression with quantitative polymerase chain reaction (qPCR) (IL6, IL8, MERTK, PIK3CA), and phagocytotic activity in a microscopic assay. FV fucoidan did not influence RPE cell viability. FV fucoidan reduced the Poly I:C proinflammatory cytokine secretion of IL-6 and IL-8. In addition, it decreased the expression of IL-6 and IL-8 in RT-PCR. LPS and TNF-α reduced the expression of CD59 in Western blot, this reduction was lost under FV fucoidan treatment. Also, LPS and TNF-α reduced the expression of visual cycle protein RPE65, this reduction was again lost under FV fucoidan treatment. Furthermore, the significant reduction of barrier function after Poly I:C stimulation is ameliorated by FV fucoidan. Concerning phagocytosis, however, the inflammation-induced reduction was not improved by FV fucoidan. FV and proinflammatory milieu did not relevantly influence phagocytosis relevant gene expression either. In conclusion, we show that fucoidan from FV can reduce proinflammatory stimulation in RPE induced by toll-like receptor 3 (TLR-3) activation and is of high interest as a potential compound for early AMD treatment.

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.

Sulfated Polysaccharides from Macroalgae-A Simple Roadmap for Chemical Characterization

The marine environment presents itself as a treasure chest, full of a vast diversity of organisms yet to be explored. Among these organisms, macroalgae stand out as a major source of natural products due to their nature as primary producers and relevance in the sustainability of marine ecosystems. Sulfated polysaccharides (SPs) are a group of polymers biosynthesized by macroalgae, making up part of their cell wall composition. Such compounds are characterized by the presence of sulfate groups and a great structural diversity among the different classes of macroalgae, providing interesting biotechnological and therapeutical applications. However, due to the high complexity of these macromolecules, their chemical characterization is a huge challenge, driving the use of complementary physicochemical techniques to achieve an accurate structural elucidation. This review compiles the reports (2016-2021) of state-of-the-art methodologies used in the chemical characterization of macroalgae SPs aiming to provide, in a simple way, a key tool for researchers focused on the structural elucidation of these important marine macromolecules.

Characterization and therapeutic effect of Sargassum coreanum fucoidan that inhibits lipopolysaccharide-induced inflammation in RAW 264.7 macrophages by blocking NF-κB signaling

Inflammation is a complex host-protective response against harmful stimuli involving macrophage activation that results in secretion of inflammatory mediators, like nitric oxide (NO), pro-inflammatory cytokines, and prostaglandin E2 (PGE2). In this study, we evaluated fucoidan isolated using Viscozyme-assisted enzymatic extraction of Sargassum coreanum extract against lipopolysaccharide (LPS)-stimulated inflammation in RAW 264.7 macrophages and zebrafish model. Among the fucoidan fractions isolated using ion exchange chromatography, SCVF5 showed the highest sulfate and fucose contents based on chemical composition and monosaccharide analysis. Fourier-transform infrared (FT-IR) spectroscopy confirmed the presence of sulfate esters by the stretching vibrations of the SO peak at 1240 cm-1. SCVF5 showed anti-inflammatory effects by inhibiting NO and PGE2 generation in LPS-stimulated RAW 264.7 macrophages by downregulating inducible NO synthase and cyclooxygenase-2 expression. Treatment with SCVF5 suppressed pro-inflammatory cytokine production, such as TNF-α, (IL)-1β, and IL-6 by modulating the nuclear factor-kappa B signaling cascade in LPS-induced RAW 264.7 cells. Furthermore, in vivo results showed that SCVF5 can potentially downregulate LPS-induced toxicity, cell death, and NO production in LPS-induced zebrafish model. Collectively, these results suggest that S. coreanum fucoidan has remarkable anti-inflammatory activity in vitro and in vivo and may have potential applications in the functional food, cosmetic, and pharmaceutical industries.

FTIR Characterization of Sulfated Polysaccharides Obtained from Macrocystis integrifolia Algae and Verification of Their Antiangiogenic and Immunomodulatory Potency In Vitro and In Vivo

The aim of this study was to evaluate the antiangiogenic and immunomodulatory potential of sulfated polysaccharides from the marine algae Macrocystis integrifolia characterized by FTIR. The cytotoxicity of sulfated polysaccharides was evaluated using the 3-(4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide (MTT) assay. Antiangiogenic activity was evaluated using the chicken chorioallantoic membrane (CAM) assay. Immunomodulatory activity was determined on macrophage functionality and allergic response. The results showed that sulfated polysaccharides significantly decreased angiogenesis in chicken chorioallantoic membranes (p < 0.05). Likewise, they inhibited in vivo chemotaxis and in vitro phagocytosis, the transcription process of genes that code the enzymes cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2) and nitric oxide synthase-2 (NOS-2) and the nuclear factor kappa-light chain enhancer of activated B cells (NF-κB), showing immunomodulatory properties on the allergic response, as well as an in vivo inhibitory effect in the ovalbumin-induced inflammatory allergy model (OVA) and inhibited lymphocyte proliferation specific to the OVA antigen in immunized mice. Finally, these compounds inhibited the histamine-induced skin reaction in rats, the production of immunoglobulin E (IgE) in mice, and the passive response to skin anaphylaxis in rats. Therefore, the results of this research showed the potential of these compounds to be a promising source for the development of antiangiogenic and immunomodulatory drugs.

A Review on Fucoidan Structure, Extraction Techniques, and Its Role as an Immunomodulatory Agent

Functional ingredients for human health have recently become the focus of research. One such potentially versatile therapeutic component is fucose-containing sulfated polysaccharides (FCSPs), referred to as fucoidans. The exploitation of marine brown algae provides a rich source of FCSPs because of their role as a structural component of the cell wall. Fucoidans are characterized by a sulfated fucose backbone. However, the structural characterization of FCSPs is impeded by their structural diversity, molecular weight, and complexity. The extraction and purification conditions significantly influence the yield and structural alterations. Inflammation is the preliminary response to potentially injurious inducements, and it is of the utmost importance for modulation in the proper direction. Improper manipulation and/or continuous stimuli could have detrimental effects in the long run. The web of immune responses mediated through multiple modulatory/cell signaling components can be addressed through functional ingredients, benefiting patients with no side effects. In this review, we attempted to address the involvement of FCSPs in the stimulation/downregulation of immune response cell signaling. The structural complexity and its foremost influential factor, extraction techniques, have also attracted attention, with concise details on the structural implications of bioactivity.

3-Bromo-4,5-dihydroxybenzaldehyde Isolated from Polysiphonia morrowii Suppresses TNF-α/IFN-γ-Stimulated Inflammation and Deterioration of Skin Barrier in HaCaT Keratinocytes

Polysiphonia morrowii is a well-known red alga that has promising pharmacological characteristics. The current study evaluates the protective effect of 3-bromo-4,5-dihydroxybenzaldehyde (BDB) isolated from P. morrowii on tumor necrosis factor (TNF)-α/interferon (IFN)-γ-stimulated inflammation and skin barrier deterioration in HaCaT keratinocytes. The anti-inflammatory effect of BDB in TNF-α/IFN-γ-stimulated HaCaT keratinocytes is evaluated by investigating nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways, inflammatory cytokines, and chemokines. Further, the interaction between BDB and the skin barrier functions in stimulated HaCaT keratinocytes is investigated. The findings of the study reveal that BDB dose-dependently increases cell viability while decreasing intracellular reactive oxygen species (ROS) production. BDB downregulates the expression of inflammatory cytokines, interleukin (IL)-6, -8, -13, IFN-γ, TNF-α, and chemokines, Eotaxin, macrophage-derived chemokine (MDC), regulated on activation, normal T cells expressed and secreted (RANTES), and thymus and activation-regulated chemokine (TARC) by modulating the MAPK and NF-κB signaling pathways in TNF-α/IFN-γ-stimulated HaCaT keratinocytes. Furthermore, BDB increases the production of skin hydration proteins and tight junction proteins in stimulated HaCaT keratinocytes by preserving skin moisturization and tight junction stability. These findings imply that BDB exhibits a protective ability against inflammation and deterioration of skin barrier via suppressing the expression of inflammatory signaling in TNF-α/IFN-γ-stimulated HaCaT keratinocytes.

Two Ascophyllum nodosum Fucoidans with Different Molecular Weights Inhibit Inflammation via Blocking of TLR/NF-κB Signaling Pathway Discriminately

The present study aimed to clarify the potential mechanism of fucoidans found in Ascophyllum nodosum on anti-inflammation and to further explore the relationship between their structures and anti-inflammation. Two novel fucoidans named ANP-6 and ANP-7 and found in A. nodosum, were separated and purified and their structures were elucidated by HPGPC, HPLC, GC-MS, FT-IR, NMR, and by the Congo red test. They both possessed a backbone constructed of →2)-α-L-Fucp4S-(1→, →3)-α-L-Fucp2S4S-(1→, →6)-β-D-Galp-(1→, and →3,6)-β-D-Galp4S-(1→ with branches of →2)-α-L-Fucp4S-(1→ and →3)-β-D-Galp-(1→. Moreover, ANP-6 and ANP-7 could prevent the inflammation of the LPS-stimulated macrophages by suppressing the NO production and by regulating the expressions of iNOS, COX-2, TNF-α, IL-1β, IL-6, and IL-10. Their inhibitory effects on the TLR-2 and TLR-4 levels suggest that they inhibit the inflammation process via the blocking of the TLR/NF-κB signal transduction. In addition, ANP-6, with a molecular weight (63.2 kDa), exhibited stronger anti-inflammatory capabilities than ANP-7 (124.5 kDa), thereby indicating that the molecular weight has an influence on the anti-inflammatory effects of fucoidans.

Anti-Fine Dust Effect of Fucoidan Extracted from Ecklonia maxima Laves in Macrophages via Inhibiting Inflammatory Signaling Pathways

Brown seaweeds contain fucoidan, which has numerous biological activities. Here, the anti-fine-dust activity of fucoidan extracted from Ecklonia maxima, an abundant brown seaweed from South Africa, was explored. Fourier transmittance infrared spectroscopy, high-performance anion-exchange chromatography with pulsed amperometric detection analysis of the monosaccharide content, and nuclear magnetic resonance were used for the structural characterization of the polysaccharides. The toll-like receptor (TLR)-mediated nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways were evaluated. The results revealed that E. maxima purified leaf fucoidan fraction 7 (EMLF7), which contained the highest sulfate content, showed the best anti-inflammatory activity by attenuating the TLR-mediated NF-κB/MAPK protein expressions in the particulate matter-stimulated cells. This was solidified by the successful reduction of Prostaglandin E2, NO, and pro-inflammatory cytokines, such as TNF-α, IL-6, and IL-1β. The current findings confirm the anti-inflammatory activity of EMLF7, as well as the potential use of E. maxima as a low-cost fucoidan source due to its abundance. This suggests its further application as a functional ingredient in consumer products.

Mechanism of Ser-Ala-Gly-Pro-Ala-Phe treatment with a pulsed electric field to improve ethanol-induced gastric mucosa injury in mice

This paper focused on the mechanism of Ser-Ala-Gly-Pro-Ala-Phe (SAGPAF) treatment to improve gastric mucosal injury in mice. A gastric mucosa injury model induced by ethanol was established, and the superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, nitric oxide (NO) content and myeloperoxidase (MPO) level were determined. We performed macroscopic and histopathological evaluation of the gastric organs. Moreover, we analyzed the mechanism of SAGPAF treatment by western blotting. Compared with the model group, the SOD activity and NO content in the medium-dose and high-dose SAGPAF groups of treated with 10 kV cm^-1 field intensity were significantly increased. The MDA content and MPO level were decreased significantly. They significantly reduced the gastric mucosal injury induced by ethanol (21.17 ± 3.51% and 13.99 ± 2.00%) and the histopathological scores (3.83 ± 0.40 and 4.33 ± 0.37) (P < 0.05). Western blotting analysis showed that SAGPAF after pulsed electric field (PEF) treatment improved gastric injury by reducing protein phosphorylation. These findings provided strong evidence that PEF-treated SAGPAF enhanced the gastric mucosal barrier function by inhibiting the activation of the mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B (NF-κB) signaling pathways, reducing the ethanol-induced inflammatory response and oxidative stress.

Anti-Inflammatory Effect of Sulfated Polysaccharides Isolated from Codium fragile In Vitro in RAW 264.7 Macrophages and In Vivo in Zebrafish

In this study, the anti-inflammatory activity of sulfated polysaccharides isolated from the green seaweed Codium fragile (CFCE-PS) was investigated in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and zebrafish. The results demonstrated that CFCE-PS significantly increased the viability of LPS-induced RAW 264.7 cells in a concentration-dependent manner. CFCE-PS remarkably and concentration-dependently reduced the levels of inflammatory molecules including prostaglandin E₂, nitric oxide (NO), interleukin-1 beta, tumor necrosis factor-alpha, and interleukin-6 in LPS-stimulated RAW 264.7 cells. In addition, in vivo test results indicated that CFCE-PS effectively reduced reactive oxygen species, cell death, and NO levels in LPS-stimulated zebrafish. Thus, these results indicate that CFCE-PS possesses in vitro and in vivo anti-inflammatory activities and suggest it is a potential ingredient in the functional food and pharmaceutical industries.

Fucoidan-loaded nanofibrous scaffolds promote annulus fibrosus repair by ameliorating the inflammatory and oxidative microenvironments in degenerative intervertebral discs

Tissue engineering holds potential in the treatment of intervertebral disc degeneration (IDD). However, implantation of tissue engineered constructs may cause foreign body reaction and aggravate the inflammatory and oxidative microenvironment of the degenerative intervertebral disc (IVD). In order to ameliorate the adverse microenvironment of IDD, in this study, we prepared a biocompatible poly (ether carbonate urethane) urea (PECUU) nanofibrous scaffold loaded with fucoidan, a natural marine bioactive polysaccharide which has great anti-inflammatory and antioxidative functions. Compared with pure PECUU scaffold, the fucoidan-loaded PECUU nanofibrous scaffold (F-PECUU) decreased the gene and protein expression related to inflammation and the oxidative stress in the lipopolysaccharide (LPS) induced annulus fibrosus cells (AFCs) significantly (p<0.05). Especially, gene expression of Ill 6 and Ptgs2 was decreased by more than 50% in F-PECUU with 3.0 wt% fucoidan (HF-PECUU). Moreover, the gene and protein expression related to the degradation of extracellular matrix (ECM) were reduced in a fucoidan concentration-dependent manner significantly, with increased almost 3 times gene expression of Col1a2 and Acan in HF-PECUU. Further, in a 'box' defect model, HF-PECUU decreased the expression of COX-2 and deposited more ECM between scaffold layers when compared with pure PECUU. The disc height and nucleus pulposus hydration of repaired IVD reached up to 75% and 85% of those in the sham group. In addition, F-PECUU helped to maintain an integrate tissue structure with a similar compression modulus to that in sham group. Taken together, the F-PECUU nanofibrous scaffolds showed promising potential to promote AF repair in IDD treatment by ameliorating the harsh degenerative microenvironment. STATEMENT OF SIGNIFICANCE: Annulus fibrosus (AF) tissue engineering holds potential in the treatment of intervertebral disc degeneration (IDD), but is restricted by the inflammatory and oxidative microenvironment of degenerative disc. This study developed a biocompatible polyurethane scaffold (F-PECUU) loaded with fucoidan, a marine bioactive polysaccharide, for ameliorating IDD microenvironment and promoting disc regeneration. F-PECUU alleviated the inflammation and oxidative stress caused by lipopolysaccharide and prevented extracellular matrix (ECM) degradation in AF cells. In vivo, it promoted ECM deposition to maintain the height, water content and mechanical property of disc. This work has shown the potential of marine polysaccharides-containing functional scaffolds in IDD treatment by ameliorating the harsh microenvironment accompanied with disc degeneration.

Bioactive Potential of Brown Algae

Marine-derived natural products are rich source of secondary metabolites with huge potentials including novel therapeutic agents. Marine algae are considered to be a good source of secondary metabolites with versatile bioactivities. During the last few decades, researches related to natural products obtained from brown algae have remarkably escalated as they contain active compounds with varied biologically activities like antimicrobial, anticancer, antioxidant, anti-inflammatory, antidiabetic, and antiparasitic properties. The main bioactive components such as phlorotannin, fucoxanthin, alginic acid, fucoidan, and laminarin have been briefly discussed here, together with their composition and biological activities. In this review, the biological function of extracts and the metabolites of brown algae as well as their pharmacological impacts with the description of the possible mechanism of their action are described and discussed. Also, this study is expected to examine the multifunctional properties of brown algae that facilitate natural algal products, including the ability to integrate these functional properties in a variety of applications.

Polyopes affinis Suppressed IFN-γ- and TNF-α-Induced Inflammation in Human Keratinocytes via Down-Regulation of the NF-κB and STAT1 Pathways

Polyopes affinis is a red algal species commonly found on the South coast and near Jeju Island, Korea. This study aimed to determine whether P. affinis extracts can inhibit the pathogenesis of T-helper-2 (Th2)-mediated inflammation in a human keratinocyte cell line of atopic dermatitis (AD). Cells were incubated with 10 ng/mL of interferon gamma (IFN-γ) and 10 ng/mL of tumor necrosis factor-alpha (TNF-α) at various concentrations of PAB (10, 30, and 60 µg/mL) and PAA (100, 500, and 1000 µg/mL) extracts. A gene-ontology (GO)-enrichment analysis revealed that PAB significantly enriched the genes associated with biological processes such as cell adhesion, immune response, inflammation, and chemokine-mediated pathways. PAB suppressed the expression of the secretory proteins and mRNAs that are associated with the thymus and the production of activation-regulated chemokines (TARC/CCL17) and macrophage-derived chemokines (MDC/CCL22). The effect of the extract on mitogen-activated protein kinases (MAPKs) was related to its inhibition of TARC/CCL17 and MDC/CCL22 production by blocking NF-κB and STAT1 activation. These results suggest that seaweed extract may improve AD by regulating pro-inflammatory chemokines. In conclusion, we first confirmed the existence of phloroglucinol, a polyphenol formed from a precursor called phlorotannin, which is present in PAB, and this result proved the possibility of PAB being used as a treatment for AD.

Fabrication of Sulfated Heterosaccharide/Poly (Vinyl Alcohol) Hydrogel Nanocomposite for Application as Wound Healing Dressing

Nowadays, natural polysaccharides-based hydrogels have achieved promising results as dressings to promote skin healing. In the present study, we prepared a novel hydrogel nanocomposite with poly(vinyl alcohol) (PVA) and sulfated heterosaccharide (UF), named UPH. The SEM results showed that the UPH had dense porous structures with a high porosity and a specific surface area. The UPH had a good swelling property, which can effectively adsorb exudate and keep the wound moist. The in vitro experiments results showed that the UPH was non-cytotoxic and could regulate the inflammatory response and promote the migration of fibroblasts significantly. The phenotypic, histochemistry, and Western blot analyses showed UPH treatment accelerated the wound healing and recovery of skin tissue at wound sites in a C57BL/6 mouse model. Furthermore, the UPH could promote the inflammation process to onset earlier and last shorter than that in a normal process. Given its migration-promoting ability and physicochemical properties, the UPH may provide an effective application for the treatment and management of skin wounds.

Wheat oligopeptides enhance the intestinal mucosal barrier and alleviate inflammation via the TLR4/Myd88/MAPK signaling pathway in aged mice

Background

Aging can induce oxidative stress, inflammation and mucosal impairment, and few works have been conducted to investigate the protective effects of WP on the natural intestinal aging process.

Objective

The present work aimed to examine the protective effect of wheat oligopeptides (WP) on intestine mucosal impairment in aged mice, and investigate the potential antioxidation, anti-inflammatory effects of WP.

Design

Seventy-two aged mice (24 months old) were randomly divided into six groups, 12 for each group. Twelve young mice (6 months old) were regarded as the young control group. WP (25, 50, 100, 200, or 400 mg/kg) or distilled water were administered daily by gavage for 30 days.

Results

Histological observations showed that intestinal mucosal degeneration was attenuated by WP pretreatment. WP exhibited remarkable antioxidant activity via increasing superoxide dismutase, glutathione peroxidase, total antioxidant capacity and catalase activities, and decreasing the malondialdehyde levels in small intestine mucosa. WP pretreatment significantly suppressed intestinal mucosa inflammation through the reduction of TNF-α, TGF-β, IFN-γ IL-1β and IL-6. WP markedly protect the intestinal mucosal barrier by decreasing the ICAM-1 level, and increasing ZO-1 and JAMA-A levels. WP significantly down-regulated protein expression levels of TLR4, Myd88, and MAPK, suggesting that WP have a potential effect on inhibiting aging-induced inflammatory responses by blocking TLR4/Myd88/MAPK signal transduction.

Conclusion

WP administration effectively alleviated intestinal mucosal impairment in aged mice. The potential mechanism was associated with enhancement of antioxidation and anti-inflammatory action and protection of the intestinal mucosal barrier.

Fucoidan Isolated from Sargassum confusum Suppresses Inflammatory Responses and Oxidative Stress in TNF-α/IFN-γ- Stimulated HaCaT Keratinocytes by Activating Nrf2/HO-1 Signaling Pathway

Recent studies have revealed that marine brown seaweeds contain numerous bioactive compounds which exhibit various bioactivities. The present study investigated the effect of low molecular weight fucoidan (SCF) isolated from Sargassum confusum, a brown alga, on inflammatory responses and oxidative stress in HaCaT keratinocytes stimulated by tumor necrosis factor (TNF)-α/interferon (IFN)-γ. SCF significantly increased the cell viability while decreasing the intracellular reactive oxygen species (ROS) production in TNF-α/IFN-γ-stimulated HaCaT keratinocytes. In addition, SCF effectively reduced inflammatory cytokines (interleukin (IL)-1β, IL-6, IL-8, IL-13, TNF-α, and IFN-γ) and chemokines (Eotaxin, macrophage-derived chemokine (MDC), regulated on activation, normal T cell expressed and secreted (RANTES), and thymus and activation-regulated chemokine (TARC)) expression, by down-regulating the expression of epithelial and epidermal innate cytokines (IL-25, IL-33, and thymic stromal lymphopoietin (TSLP)). Furthermore, SCF suppressed the activation of TNF-α/IFN-γ-stimulated mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways, while activating the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway. The cytoprotective effect of SCF against TNF-α/IFN-γ stimulation was considerably reduced upon inhibition of HO-1 activity by ZnPP. Overall, these results suggest that SCF effectively suppressed inflammatory responses and oxidative stress in TNF-α/IFN-γ-stimulated HaCaT keratinocytes via activating the Nrf2/HO-1 signaling pathway.

HD-13 Induces Swine Pneumonia Progression via Activation of TLR9

Swine pneumonia commonly known as swine pasteurellosis is an infectious disease of swine caused by Pasteurella multocida infection. It has been reported that Toll-like receptors (TLRs) play a vital role in swine pneumonia progression. However, the underlying mechanism has not been elucidated. This research was aimed at investigating the molecular mechanism by which TLR9 regulates swine pneumonia progression. Our findings illustrated that the HD-13 strain of Pasteurella multocida D (HD-13) accelerated TLR9 expression in porcine alveolar macrophage 3D4/21 cells; HD-13 activated the inflammatory response via accelerating TLR9 expression. Mechanistically, HD-13 activated mitogen-activated protein kinase (MAPK) and nuclear factor kB (NF-κB) signals. In conclusion, HD-13 may activate MAPK and NF-κB pathways via accelerating TLR9 expression, thereby accelerating the inflammatory response in the progression of swine pneumonia. TLR9 may serve as a novel therapeutic target for swine pneumonia. Our research may provide a theoretical basis for the prevention and treatment of swine pneumonia.

Structural characteristics, anti-proliferative and immunomodulatory activities of a purified polysaccharide from Lactarius volemus Fr

Lactarius volemus Fr. is an edible mushroom widely consumed in China. Polysaccharide is an important nutritional component of L. volemus. This research aimed to isolate the polysaccharide from L. volemus and study its structure and bioactivities. A purified polysaccharide was identified and named as LVF-I whose primary structure was proposed considering the comprehensive results of monosaccharide composition, periodate oxidation-smith degradation, methylation analysis, FT-IR and 1D/2D NMR spectroscopy. Then the immunomodulation of LVF-I and its inhibition effect on H1299 and MCF-7 cells were investigated. Results showed that LVF-I (12,894 Da) contained fucose, mannose, glucose and galactose. It had a backbone consisting of →4)-α-D-Glcp-(1→, →6)-β-D-Manp-(1→, →6)-α-D-Galp-(1 → and →4)-β-D-Manp-(1→. And its side chains were branched at C2 of →4)-β-D-Manp-(1 → by →6)-α-D-Galp-(1→, α-D-Glcp-(1→, α-D-Galp-(1 → and α-L-Fucp-(1→. LVF-I (250-1000 μg/mL) could inhibit the proliferation of H1299 and MCF-7 cells, while enhance the proliferative response of splenocyte and the phagocytic ability of RAW264.7. Furthermore, LVF-I (250-1000 μg/mL) significantly induced the secretion of nitric oxide, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) by up-regulating their mRNA expression in macrophages. These results suggested that LVF-I had the potential to be developed as antitumor or immunomodulatory agents by inhibiting the proliferation of tumor cells and stimulating macrophages-mediated immune responses.

Anti-Inflammatory Mechanisms of Fucoidans to Treat Inflammatory Diseases: A Review

Fucoidans are sulfated heteropolysaccharides found in the cell walls of brown seaweeds (Phaeophyceae) and in some marine invertebrates. Generally, fucoidans are composed of significant amounts of L-fucose and sulfate groups, and lesser amounts of arabinose, galactose, glucose, glucuronic acid, mannose, rhamnose, and xylose. In recent years, fucoidans isolated from brown seaweeds have gained considerable attention owing to their promising bioactive properties such as antioxidant, immunomodulatory, anti-inflammatory, antiobesity, antidiabetic, and anticancer properties. Inflammation is a complex immune response that protects the organs from infection and tissue injury. While controlled inflammatory responses are beneficial to the host, leading to the removal of immunostimulants from the host tissues and restoration of structural and physiological functions in the host tissues, chronic inflammatory responses are often associated with the pathogenesis of tumor development, arthritis, cardiovascular diseases, diabetes, obesity, and neurodegenerative diseases. In this review, the authors mainly discuss the studies since 2016 that have reported anti-inflammatory properties of fucoidans isolated from various brown seaweeds, and their potential as a novel functional material for the treatment of inflammatory diseases.

Antiparasitic Effects of Sulfated Polysaccharides from Marine Hydrobionts

This review presents materials characterizing sulfated polysaccharides (SPS) of marine hydrobionts (algae and invertebrates) as potential means for the prevention and treatment of protozoa and helminthiasis. The authors have summarized the literature on the pathogenetic targets of protozoa on the host cells and on the antiparasitic potential of polysaccharides from red, brown and green algae as well as certain marine invertebrates. Information about the mechanisms of action of these unique compounds in diseases caused by protozoa has also been summarized. SPS is distinguished by high antiparasitic activity, good solubility and an almost complete absence of toxicity. In the long term, this allows for the consideration of these compounds as effective and attractive candidates on which to base drugs, biologically active food additives and functional food products with antiparasitic activity.

Brown Algae Carbohydrates: Structures, Pharmaceutical Properties, and Research Challenges

Brown algae (Phaeophyceae) have been consumed by humans for hundreds of years. Current studies have shown that brown algae are rich sources of bioactive compounds with excellent nutritional value, and are considered functional foods with health benefits. Polysaccharides are the main constituents of brown algae; their diverse structures allow many unique physical and chemical properties that help to moderate a wide range of biological activities, including immunomodulation, antibacterial, antioxidant, prebiotic, antihypertensive, antidiabetic, antitumor, and anticoagulant activities. In this review, we focus on the major polysaccharide components in brown algae: the alginate, laminarin, and fucoidan. We explore how their structure leads to their health benefits, and their application prospects in functional foods and pharmaceuticals. Finally, we summarize the latest developments in applied research on brown algae polysaccharides.

Anti-inflammatory effect of a polysaccharide fraction from Craterellus cornucopioides in LPS-stimulated macrophages

Immunocytes-involved inflammation is considered to modulate the damage in various diseases. Oxidative stress is initiated by oxidative agents such as LPS and ROS, which are strongly involved in chronic inflammation. Our previous study found that a polysaccharide fraction from Craterellus cornucopioides (CCPP-1) showed good antioxidant activity. However, the anti-inflammatory effect of CCPP-1 was still elusive. The objective of this study was to evaluate the anti-inflammatory activity of CCPP-1 and its potential mechanism in LPS-stimulated RAW264.7 macrophages. The results showed that CCPP-1 could inhibit LPS-induced ROS and NO accumulation. Additionally, CCPP-1 could decrease pro-inflammatory cytokines production (TNF-α, IL-1β, and IL-18) and inflammatory mediator (iNOS) expression, which might be associated with its capacity to inhibit NF-κB signaling pathway and NLRP3 inflammasome activation. Therefore, this study suggested that CCPP-1 had an ameliorative effect on the inflammation response and was potential to develop into functional food for treating chronic inflammation. PRACTICAL APPLICATIONS: Craterellus cornucopioides is an edible fungus widely distributed in Southwestern China. It was reported that C. cornucopioides polysaccharide (CCPP-1), as important active ingredient, showed good antioxidant activity. However, the anti-inflammatory effect was still elusive. This study showed that CCPP-1 possessed anti-inflammatory activity. The molecular mechanism might be associated with its capacity to inhibit NF-κB signaling pathway and NLRP3 inflammasome activation. Therefore, polysaccharides from C. cornucopioides have potential to develop into functional food to combat inflammatory condition and thus indirectly halt the progression of various inflammatory response-related chronic diseases.

Potential benefits of dietary seaweeds as protection against COVID-19

The coronavirus disease 2019 (COVID-19) pandemic in Japan is not as disastrous as it is in other Western countries, possibly because of certain lifestyle factors. One such factor might be the seaweed-rich diet commonly consumed in Japan. COVID-19 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which binds to angiotensin-converting enzyme 2 (ACE2) on the cell surface and downregulates ACE2, likely elevating the ratio of angiotensin-converting enzyme (ACE) to ACE2. The overreaction of the immune system, combined with the cytokine storm and ACE dominance, is purported to cause the condition of COVID-19 patients to deteriorate rapidly. Dietary seaweeds contain numerous components, including ACE inhibitory peptides, soluble dietary fibers (eg, fucoidan, porphyran), omega-3 fatty acids, fucoxanthin, fucosterol, vitamins D3 and B12, and phlorotannins. These components exert antioxidant, anti-inflammatory, and antiviral effects directly as well as indirectly through prebiotic effects. It is possible that ACE inhibitory components could minimize the ACE dominance caused by SARS-CoV-2 infection. Thus, dietary seaweeds might confer protection against COVID-19 through multiple mechanisms. Overconsumption of seaweeds should be avoided, however, as seaweeds contain high levels of iodine.

Fucoidans as Scientifically and Commercially Important Algal Polysaccharides

As a highly bioactive seaweed substance with many promising physiological activities, fucoidan has attracted attention from many industries all over the world [...].

In Vitro and In Vivo Anti-Inflammatory Effects of Sulfated Polysaccharides Isolated from the Edible Brown Seaweed, Sargassum fulvellum

In the present study, the in vitro and in vivo anti-inflammatory effects of the sulfated polysaccharides isolated from Sargassum fulvellum (SFPS) were evaluated in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and zebrafish. The results indicated that SFPS improved the viability of LPS-stimulated RAW 264.7 macrophages from 80.02 to 86.80, 90.09, and 94.62% at the concentration of 25, 50, and 100 µg/mL, respectively. Also, SFPS remarkably and concentration-dependently decreased the production levels of inflammatory molecules including nitric oxide (NO), tumor necrosis factor-alpha, prostaglandin E2, interleukin-1 beta, and interleukin-6 in LPS-treated RAW 264.7 macrophages. In addition, SFPS significantly inhibited the expression levels of cyclooxygenase-2 and inducible nitric oxide synthase in LPS-treated RAW 264.7 macrophages. Furthermore, the in vivo test results indicated that SFPS improved the survival rate of LPS-treated zebrafish from 53.33 to 56.67, 60.00, and 70.00% at the concentration of 25, 50, and 100 µg/mL, respectively. In addition, SFPS effectively reduced cell death, reactive oxygen species, and NO levels in LPS-stimulated zebrafish. Taken together, these results suggested that SFPS possesses strong in vitro and in vivo anti-inflammatory activities, and could be used as an ingredient to develop anti-inflammatory agents in the functional food and pharmaceutical industries.

Ecklonia cava Attenuates PM2.5-Induced Cognitive Decline through Mitochondrial Activation and Anti-Inflammatory Effect

To evaluate the effects of Ecklonia cava (E. cava) on ambient-pollution-induced neurotoxicity, we used a mouse model exposed to particulate matter smaller than 2.5 µm in aerodynamic diameter (PM2.5). The intake of water extract from E. cava (WEE) effectively prevented the learning and memory decline. After a behavioral test, the toll-like receptor (TLR)-4-initiated inflammatory response was confirmed by PM2.5 exposure in the lung and brain tissues, and the WEE was regulated through the inhibition of nuclear factor-kappa B (NF-κB)/inflammasome formation signaling pathway and pro-inflammatory cytokines (IL-6 and IFN-γ). The WEE also effectively improved the PM2.5-induced oxidative damage of the lungs and brain through the inhibition of malondialdehyde (MDA) production and the activation of mitochondrial activity (mitochondrial ROS content, mitochondria membrane potential (MMP), adenosine triphosphate (ATP) content, and mitochondria-mediated apoptotic molecules). In particular, the WEE regulated the cognition-related proteins (a decreased amyloid precursor protein (APP) and p-Tau, and an increased brain-derived neurotrophic factor (BDNF)) associated with PM2.5-induced cognitive dysfunction. Additionally, the WEE prevented the inactivation of acetylcholine (ACh) synthesis and release as a neurotransmitter by regulating the acetylcholinesterase (AChE) activity, choline acetyltransferase (ChAT), and ACh receptor (AChR)-α3 in the brain tissue. The bioactive compounds of the WEE were detected as the polysaccharide (average Mw; 160.13 kDa) and phenolic compounds including 2'-phloroeckol.

Chlamydia trachomatis glycogen synthase promotes MAPK-mediated proinflammatory cytokine production via TLR2/TLR4 in THP-1 cells

AIMS

To investigate the roles and mechanisms of C. trachomatis glycogen synthase (GlgA) in regulating the inflammatory response in THP-1 cells.

MAIN METHODS

In this work, after THP-1 cells were stimulated with GlgA, transcript and protein expression levels were measured by qRT-PCR and ELISA, respectively. Western blotting and immunofluorescence were used to determine the signaling pathway involved in the inflammatory mechanism.

KEY FINDINGS

GlgA elicited the expression of interleukin-8 (IL-8), interleukin-1beta (IL-1β) and tumor necrosis factor alpha (TNF-α) in THP-1 cells, and the blockade of TLR2 and TLR4 signaling abrogated the induction of IL-8, TNF-α and IL-1β expression. Similarly, IL-8, IL-1β and TNF-α secretion was reduced by transfection with a dominant negative plasmid (pDeNyhMyD88). Moreover, Western blotting and immunofluorescence experiments further validated that MAPKs and NF-кB signaling are involved in the transcription and translation of these cytokines. Treatment of the cells with ERK and JNK inhibitors dramatically attenuated the induction of IL-8, IL-1β and TNF-α.

SIGNIFICANCE

These results suggest that GlgA contributes to inflammation during C. trachomatis infection via the TLR2, TLR4 and MAPK/NF-кB pathways, which may enhance our understanding of the pathogenesis of C. trachomatis.

Construction and analysis for dys-regulated lncRNAs and mRNAs in LPS-induced porcine PBMCs

Long non-coding RNAs (lncRNAs) are emerging as key regulators in inflammation. However, their functions and profiles in LPS-induced inflammation in pigs are largely unknown. In this study, we profiled global lncRNA and mRNA expression changes in PBMCs treated with LPS using the lncRNA-seq technique. In total 43 differentially expressed (DE) lncRNAs and 1082 DE mRNAs were identified in porcine PBMCs after LPS stimulation. Functional enrichment analysis on DE mRNAs indicated these genes were involved in inflammation-related signaling pathways, including cytokine–cytokine receptor interaction, TNF-α, NF-κB, Jak-STAT and TLR signaling pathways. In addition, co-expression network and function analysis identified the potential lncRNAs related to inflammatory response and immune response. The expressions of eight lncRNAs (ENSSSCT00000045208, ENSSSCT00000051636, ENSSSCT00000049770, ENSSSCT00000050966, ENSSSCT00000047491, ENSSSCT00000049750, ENSSSCT00000054262 and ENSSSCT00000044651) were validated in the LPS-treated PBMCs by quantitative real-time PCR (qRT-PCR). In LPS-challenged piglets, we identified that expression of three lncRNAs (ENSSSCT00000051636, ENSSSCT00000049770, and ENSSSCT00000047491) was significantly up-regulated in liver, spleen and jejunum tissues after LPS challenge, which indicated that these lncRNAs might be important regulators for inflammation. This study provides the first lncRNA and mRNA transcriptomic landscape of LPS-mediated changes in porcine PBMCs, which might provide potential insights into lncRNAs involved in regulating inflammation in pigs.

Chlorogenic acid supplementation ameliorates hyperuricemia, relieves renal inflammation, and modulates intestinal homeostasis

Hyperuricemia (HUA) is induced by abnormal purine metabolism and elevated serum uric acid (UA) concentrations, and it is often accompanied by inflammatory responses and intestinal disorders. This study aims to assess the protective effects of chlorogenic acid (CGA) on HUA in mice. CGA or allopurinol was given to mice with HUA induced by hypoxanthine and potassium oxonate. CGA lowered the levels of UA, blood urea nitrogen (BUN), creatinine (CR), AST, and ALT; inhibited xanthine oxidase (XOD) activity; and downregulated the mRNA expression of UA secretory proteins in HUA mice. Moreover, CGA significantly reduced serum lipopolysaccharides (LPS) levels and the mRNA expression of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, NOD-like receptor superfamily pyrin domain containing 3 (NLRP3), and caspase-1, and it inhibited the activation of the toll-like receptor 4/myeloid differentiation factor 88/nuclear factor kappa B (TLR4/MyD88/NF-κB) signaling pathway in the kidney, resulting in inflammation relief in HUA mice. In addition, CGA treatment increased the production of fecal short-chain fatty acids (SCFAs) in HUA mice. Additional investigations showed that CGA significantly lowered the mRNA expression of ileal IL-1β and IL-6, and it increased the mRNA expression of intestinal tight junction proteins (zonula occludens-1 (ZO-1) and occludin). Also, CGA increased the relative abundance of SCFA-producing bacteria, including Bacteroides, Prevotellaceae UGC-001, and Butyricimonas, and it reversed the purine metabolism and glutamate metabolism functions of gut microbiota. In conclusion, CGA may be a potential candidate for relieving the symptoms of HUA and regulating its associated inflammatory responses and intestinal homeostasis.

Fucoidans as Potential Therapeutics for Age-Related Macular Degeneration-Current Evidence from In Vitro Research

Age-related macular degeneration (AMD) is the major reason for blindness in the industrialized world with limited treatment options. Important pathogenic pathways in AMD include oxidative stress and vascular endothelial growth factor (VEGF) secretion. Due to their bioactivities, fucoidans have recently been suggested as potential therapeutics. This review gives an overview of the recent developments in this field. Recent studies have characterized several fucoidans from different species, with different molecular characteristics and different extraction methods, in regard to their ability to reduce oxidative stress and inhibit VEGF in AMD-relevant in vitro systems. As shown in these studies, fucoidans exhibit a species dependency in their bioactivity. Additionally, molecular properties such as molecular weight and fucose content are important issues. Fucoidans from Saccharina latissima and Laminaria hyperborea were identified as the most promising candidates for further development. Further research is warranted to establish fucoidans as potential therapeutics for AMD.

Anti-Inflammatory Effects of Sulfated Polysaccharide from Sargassum Swartzii in Macrophages via Blocking TLR/NF-Κb Signal Transduction

This study involves enzymatic extraction of fucoidan from Sargassum swartzii and further purification via ion-exchange chromatography. The chemical and molecular characteristics of isolated fucoidan is evaluated concerning its anti-inflammatory potential in RAW 264.7 macrophages under LPS induced conditions. Structural properties of fucoidan were assessed via FTIR and NMR spectroscopy. NO production stimulated by LPS was significantly declined by fucoidan. This was witnessed to be achieved via fucoidan acting on mediators such as iNOS and COX-2 including pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β), with dose dependent down-regulation. Further, the effect is exhibited by the suppression of TLR mediated MyD88, IKK complex, ultimately hindering NF-κB and MAPK activation, proposing its therapeutic applications in inflammation related disorders. The research findings provide an insight in relation to the sustainable utilization of fucoidan from marine brown algae S. swartzii as a potent anti-inflammatory agent in the nutritional, pharmaceutical, and cosmeceutical sectors.

A Sulfated Polysaccharide from Saccharina japonica Suppresses LPS-Induced Inflammation Both in a Macrophage Cell Model via Blocking MAPK/NF-κB Signal Pathways In Vitro and a Zebrafish Model of Embryos and Larvae In Vivo

Inflammation is a complicated host-protective response to stimuli and toxic conditions, and is considered as a double-edged sword. A sulfated Saccharinajaponica polysaccharide (LJPS) with a sulfate content of 9.07% showed significant inhibitory effects against lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophage cells and zebrafish. Its chemical and structural properties were investigated via HPLC, GC, FTIR, and NMR spectroscopy. In vitro experiments demonstrated that LJPS significantly inhibited the generation of nitric oxide (NO) and prostaglandin E2 (PGE2) via the downregulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression and suppressed pro-inflammatory cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-1β production via the nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signal pathways in LPS-induced RAW 264.7 cells. Moreover, LJPS showed strong protective effects against LPS-induced inflammatory responses in zebrafish, increasing the survival rate, reducing the heart rate and yolk sac edema size, and inhibiting cell death and the production of intracellular reactive oxygen species (ROS) and NO. Its convenience for large-scale production and significant anti-inflammatory activity indicated the potential application of LJPS in functional foods, cosmetics, and pharmaceutical industries.

Chicory ameliorates hyperuricemia via modulating gut microbiota and alleviating LPS/TLR4 axis in quail

BACKGROUND

High-purine diet can cause gut microbiota disorder, which is closely related to the occurrence of hyperuricemia (HUA). At the same time, the development of HUA is often accompanied by renal impairment. Chicory, a natural medicine, has a significant effect on lowering uric acid. However, whether its concrete mechanism is associated with the regulation of gut microbiota and renal damage is still unclear.

METHODS

Hyperuricemic quails induced by high-purine diet were used, and quails were divided into control (CON), model (MOD), and model plus high, middle, low doses of chicory. The uricosuric effect was evaluated by detecting the uric acid levels in serum and feces. Meanwhile, the morphology of intestine and kidney were observed by hematoxylin and eosin (HE) staining, and the expression of intestinal barrier junction proteins Occludin, Claudin-1 were detected by quantitative real-time polymerase chain reaction (qPCR) and western blotting. Furthermore, the latent mechanism was clarified by analyzing 16S rRNA amplicon of gut microbiota and measuring the changes of LPS/TLR4 axis inflammatory response of the kidney by western blotting and enzyme-linked immunosorbent assay (ELISA).

RESULTS

The results showed that serum uric acid levels were significantly decreased, and the feces uric acid levels were noticeably increased after the intervention of chicory. In addition, chicory could repair the damage of intestinal mucosa and improve the permeability of intestinal barrier. Moreover, the 16S rRNA sequencing analysis uncovered that chicory restored gut microbiota by increasing the probiotics flora (Bifidobacterium, Erysipelotrichaceae) and reducing the pathogenic bacteria group (Helicobacteraceae). Furthermore, it was found that chicory reduced the LPS/TLR4 axis inflammatory response by down regulating the serum LPS and TLR4/NF-κB inflammatory pathway in kidney, thus promoting the excretion of uric acid in kidney.

CONCLUSION

Chicory intervention ameliorated HUA via modulating the imbalance of gut microbiota and suppressing LPS/TLR4 axis inflammatory reaction in quail model, which may be a promising candidate for hyperuricemia-relieving properties.

Therapeutic potential of fucoidan in the reduction of hepatic pathology in murine schistosomiasis japonica

BACKGROUND

Hepatic granuloma formation and fibrosis as the consequence of tissue entrapped eggs produced by female schistosomes characterize the pathology of Schistosoma japonicum infection. It has been proposed that fucoidan, a sulfated polysaccharide existing naturally in brown seaweed Fucus vesiculosus, plays a diversified role to perform immunomodulatory activities. However, whether fucoidan functions in the host hepatic pathology is unknown and identifying the potential mechanism that is responsible for hepatic improvement is still necessary.

METHODS

We evaluated the hepatic pathology from S. japonicum-infected mice after treatment with fucoidan. qRT-PCR and immunofluorescence were used to detect the pro- or anti-inflammatory factors and the phosphorylated p65 in the livers. In addition, flow cytometry was also performed to investigate the T cell subsets in the S. japonicum-infected mice after treatment with fucoidan, and functional molecules relatively specific to Treg cells were detected in vitro. Furthermore, macrophages were treated with fucoidan in vitro and to detect the inflammatory cytokines.

RESULTS

Treatment with fucoidan significantly reduced the hepatic granuloma size and fibrosis response during S. japonicum infection. The attenuated phospho-p65 protein levels and the mRNA levels of pro-inflammatory cytokines (IL-6, IL-12 and TNF-α) were observed in the livers from fucoidan-treated S. japonicum-infected mice; however, the mRNA levels of anti-inflammatory cytokines (IL-4 and IL-13) were increased. In addition, the infiltration of Treg cells was significantly enhanced both in the livers and spleens from fucoidan-treated S. japonicum-infected mice. Consistent with this, the mRNA levels of IL-10 and TGF-β were dramatically increased in the livers from S. japonicum-infected mice after fucoidan treatment. Furthermore, in vitro stimulated splenocytes with fucoidan resulted in increasing Treg cells in splenocytes as well as the functional expression of CC chemokine receptor type 4 (CCR4) and CXC chemokine receptor type 5 (CXCR5) in Treg cells. Additionally, fucoidan promoted the mRNA levels of IL-4 and IL-13 in macrophages.

CONCLUSIONS

These findings suggest an important role of natural fucoidan in reducing hepatic pathology in the progress of S. japonicum infection with a stronger Treg response, which may reveal a new potential therapeutic strategy for hepatic disease caused by parasitic chronic infection.