Characterization and anti-tumor activity of saponin-rich fractions of South Korean sea cucumbers (Apostichopus japonicus)

Holotoxin A1 from Apostichopus japonicus inhibited oropharyngeal and intra-abdominal candidiasis by inducing oxidative damage in Candida albicans

BACKGROUND AND PURPOSE

The holotoxin A1, isolated from Apostichopus japonicus, exhibits potent antifungal activities, but the mechanism and efficacy against candidiasis are unclear. In this study we have studied the antifungal effects and mechanism of holotoxin A1 against Candida albicans and in murine oropharyngeal and intra-abdominal candidiasis.

EXPERIMENTAL APPROACH

The antifungal effect of holotoxin A1 against C. albicans was tested in vitro. To explore the antifungal mechanism of holotoxin A1, the transcriptome, ROS levels, and mitochondrial function of C. albicans was evaluated. Effectiveness and systematic toxicity of holotoxin A1 in vivo was assessed in the oropharyngeal and intra-abdominal candidiasis models in mice.

KEY RESULTS

Holotoxin A1 was a potent fungicide against C. albicans SC5314, clinical strains and drug-resistant strains. Holotoxin A1 inhibited oxidative phosphorylation and induced oxidative damage by increasing intracellular accumulation of ROS in C. albicans. Holotoxin A1 induced dysfunction of mitochondria by depolarizing the mitochondrial membrane potential and reducing the production of ATP. Holotoxin A1 directly inhibited the enzymatic activity of mitochondrial complex I and antagonized with the rotenone, an inhibitor of complex I, against C. albicans. Meanwhile, the complex I subunit NDH51 null mutants showed a decreased susceptibility to holotoxin A1. Furthermore, holotoxin A1 significantly reduced fungal burden and infections with no significant systemic toxicity in oropharyngeal and intra-abdominal candidiasis in murine models.

CONCLUSION AND IMPLICATIONS

Holotoxin A1 is a promising candidate for the development of novel antifungal agents against both oropharyngeal and intra-abdominal candidiasis, especially when caused by drug-resistant strains.

Advancements and challenges in pharmacokinetic and pharmacodynamic research on the traditional Chinese medicine saponins: a comprehensive review

Recent research on traditional Chinese medicine (TCM) saponin pharmacokinetics has revealed transformative breakthroughs and challenges. The multicomponent nature of TCM makes it difficult to select representative indicators for pharmacokinetic studies. The clinical application of saponins is limited by their low bioavailability and short half-life, resulting in fluctuating plasma concentrations. Future directions should focus on novel saponin compounds utilizing colon-specific delivery and osmotic pump systems to enhance oral bioavailability. Optimizing drug combinations, such as ginsenosides with aspirin, shows therapeutic potential. Rigorous clinical validation is essential for practical applications. This review emphasizes a transformative era in saponin research, highlighting the need for clinical validation. TCM saponin pharmacokinetics, guided by traditional principles, are in development, utilizing multidisciplinary approaches for a comprehensive understanding. This research provides a theoretical basis for new clinical drugs and supports rational clinical medication.

Cloning and functional characterization of the oxidative squalene cyclase gene in the deep-sea holothurian Chiridota sp

Saponins derived from holothurians have high potential medicinal value. However, the de novo synthesis of the derivatization of triterpenes is still unclear. Oxidative squalene cyclase (OSC) can catalyze 2,3-Oxidosqualene into diverse products that serve as important precursors for triterpene synthesis. However, the function of theOSCgene in Chiridotasp. hasnot been elucidated. In this study, an OSCgenederived from the deep-sea holothurianChiridota sp. was cloned and characterized functionally in a yeast system. The open reading frame of the OSC gene was 2086 bp, which encoded 695 amino acids. The Chiridota sp. OSC gene has a similarity of 66.89 % to the OSC of other holothurian species and 63.51 % to that of Acanthaster planci. The phylogenetic tree showed that the echinozoan OSCsclustered together, and then they formeda sister group to fungi and plant homologs. Chiridota sp. OSC catalyzed 2,3-Oxidosqualene into parkeol.Under high pressure, the relative enzymatic activity and stability of cyclase inChiridota sp. was higher than that in the shallow-sea holothurianStichopus horrens. The newly cloned OSC of Chiridota sp.provideskey information for the interpretation of the saponin synthesis pathway in deep-sea holothurians.

Chemical substances and their activities in sea cucumber Apostichopus japonicus: A review

Apostichopus japonicus, also known as Stichopus japonicus, with medicinal and food homologous figures, is a globally recognized precious ingredient with extremely high nutritional value. There is no relevant review available through literature search, so this article selects the research articles through the keywords "sea cucumber" and "Apostichopus japonicus (Stichopus japonicus)" in six professional databases, such as Wiley, PubMed, ScienceDirect, ACS, Springer, and Web of Science, from 2000 to the present, summarizing the extraction, isolation, and purification methods for the four major categories (polysaccharides, proteins and peptides, saponins, and other components) of the A. japonicus chemical substances and 10 effective biological activities of A. japonicus. Included are anticoagulation, anticancer/antitumor activities, hematopoiesis, regulation of gut microbiota, and immune regulatory activities that correspond to traditional efficacy. Literature support is provided for the development of medicines and functional foods and related aspects that play a leading role in future directions.

Comprehensive metabolomics of Philippine Stichopus cf. horrens reveals diverse classes of valuable small molecules for biomedical applications

Stichopus cf. horrens is an economically important sea cucumber species in Southeast Asia due to their presumed nutritional and medicinal benefits. However, compared to other sea cucumbers such as Apostichopus japonicus, there are no biochemical studies on which compounds contribute to the purported bioactivities of S. cf. horrens. To address this, a high-throughput characterization of the global metabolite profile of the species was performed through LC-MS/MS experiments and utilizing open-access platforms such as GNPS, XCMS, and metaboAnalyst. Bioinformatics-based molecular networking and chemometrics revealed the abundance of phospholipids such as phosphatidylcholines (PCs), phosphatidylethanolamines (PEs), phosphatidylinositols (PIs), and phosphatidylserines (PSs) in the crude samples. Body wall extracts were observed to have higher levels of structural, diacylated PCs, while the viscera have higher relative abundance of single-tail PCs and PEs that could be involved in digestion via nutrient absorption and transport for sea cucumbers. PEs and sphingolipids could also be implicated in the ecological response and morphological transformations of S. cf. horrens in the presence of predatory and other environmental stress. Interestingly, terpenoid glycosides and saponins with reported anti-cancer benefits were significantly localized in the body wall. The sulfated alkanes and sterols present in S. cf. horrens bear similarity to known kairomones and other signaling molecules. All in all, the results provide a baseline metabolomic profile of S. cf. horrens that may further be used for comparative and exploratory studies and suggest the untapped potential of S. cf. horrens as a source of bioactive molecules.

Antioxidant, Antiviral, and Anti-Inflammatory Activities of Lutein-Enriched Extract of Tetraselmis Species

Microalgae are proposed to have powerful applications for human health in the pharmaceutical and food industries. Tetraselmis species (sp.), which are green microalgae, were identified as a source of broad-spectrum health-promoting biological activities. However, the bioactivity of these species has not been elucidated. We aimed to confirm the antioxidant, antiviral, and anti-inflammatory effects of Tetraselmis sp. extract (TEE). TEE showed 2,2-diphenyl-1-picryl-hydrazyl-hydrate radical and hydrogen peroxide scavenging activities and reduced plaque formation in Vero E6 cells infected with vaccinia virus. TEE treatment also significantly inhibited nitric oxide (NO) production and improved cell viability in lipopolysaccharide (LPS)-induced RAW264.7 cells. These anti-inflammatory effects were further analyzed in LPS-induced RAW 264.7 cells and the zebrafish model. Further, TEE reduced induced NO synthase expression and proinflammatory cytokine release, including tumor necrosis factor-α, interleukin-6, and interleukin-1β, through MAPKs and NF-κB-dependent mechanisms. Further analysis revealed that TEE increased the survival rate and reduced cell death and NO production in an LPS-stimulated zebrafish model. Further, high-performance liquid chromatography revealed a strong presence of the carotenoid lutein in TEE. Overall, the results suggest that lutein-enriched TEE may be a potent antioxidant, antiviral, and anti-inflammatory agent that could be sustainably utilized in industrial applications.

Mass spectrometry analysis of saponins

Saponins are amphiphilic molecules of pharmaceutical interest and most of their biological activities (i.e., cytotoxic, hemolytic, fungicide, etc.) are associated to their membranolytic properties. These molecules are secondary metabolites present in numerous plants and in some marine animals, such as sea cucumbers and starfishes. Structurally, all saponins correspond to the combination of a hydrophilic glycan, consisting of sugar chain(s), linked to a hydrophobic triterpenoidic or steroidic aglycone, named the sapogenin. Saponins present a high structural diversity and their structural characterization remains extremely challenging. Ideally, saponin structures are best established using nuclear magnetic resonance experiments conducted on isolated molecules. However, the extreme structural diversity of saponins makes them challenging from a structural analysis point of view since, most of the time, saponin extracts consist in a huge number of congeners presenting only subtle structural differences. In the present review, we wish to offer an overview of the literature related to the development of mass spectrometry for the study of saponins. This review will demonstrate that most of the past and current mass spectrometry methods, including electron, electrospray and matrix-assisted laser desorption/ionization ionizations, gas/liquid chromatography coupled to (tandem) mass spectrometry, collision-induced dissociation including MS³ experiments, multiple reaction monitoring based quantification, ion mobility experiments, and so forth, have been used for saponin investigations with great success on enriched extracts but also directly on tissues using imaging methods.

Structural characteristics and immunostimulatory activity of sea cucumber tendon polysaccharides in cyclophosphamide-induced Balb/c mice

Sea cucumber tendon, one of the main parts of sea cucumber viscera, is widely accepted as a waste residue. In this study, a sea cucumber tendon polysaccharide (SCTPII) was purified from sea cucumber tendons and its primary structures and immunomodulatory activity were investigated. SCTPII is a triple-helix conformation homogeneous polysaccharide with a molecular weight of 3.97 × 10⁶ Da that consists of glucose and fucose with molar ratios of 92.09% and 7.91% with high thermostability. In vivo tests on immunosuppressed Balb/c mice revealed that compared with the model group, the proliferation of T cells and B cells in splenic lymphocytes of mice in the high-dose group was significantly improved by 0.92 times and 5.14 times, respectively. Additionally, SCTPII could improve the proliferation ability and phagocytosis of macrophages, as well as promoting the expression of IL-6, TNF-α and IFN-γ and enhancing the intestinal physical barrier function by increasing the protein expression of claudin-1, occludin, ZO-1 and MUC2. Furthermore, the 16S rRNA sequencing of fecal samples was performed, and gene count and α-diversity analysis revealed that SCTPs could improve the microbial community richness. In particular, SCTPs could increase the relative abundance of Lactobacillus, Bacteroides and Akkermansia and reduce the relative abundance of Lachnospiraceae_NK4A136_group and Rikenellaceae_RC9_gut_group. These results demonstrate that SCPII possesses potential immunoregulatory activities in cyclophosphamide-induced mice by regulating intestinal microbiota diversity and improving immune organs, enhancing the proliferation ability of macrophages and splenocyte proliferation, and enhancing intestinal physical barrier function, which might provide important evidence for the development and utilization of the viscera of sea cucumber.

Treatment of obese zebrafish with saringosterol acetate through AMP activated protein kinase pathway

OBJECT

 Edible Brown Seaweed Sargassum fusiforme (Harvey) Setchell, 1931 abbreviated as  Sargassum  fusiforme  was used for folk medical therapy in East Asia countries over five hundred years. Saringosterol acetate (SA) was isolated from  S. fusiforme  in our previous study and indicated various effects. However, anti-obesity activity of SA and its mechanism still unknown.  Method:  The inhibitory effect of SA, isolated from  S. fusiforme , on adipogenesis in 3T3-L1 adipocytes was investigated  in   vitro  and in zebrafish model. Cell toxicity, differentiation, signaling pathway, and lipid accumulation of SA treated 3T3-L1 adipocytes were determined. The body weight and triglyceride content of diet-induced obese (DIO) adult male zebrafish were measured from 12 to 17 weeks after fertilization.  Result:  SA attenuated the differentiation of cells and reduced lipid accumulation, and triglyceride content in the 3T3-L1 adipocytes. During the differentiation of adipocytes, SA suppressed fat accumulation and decreased the expression of signal factors responsible for adipogenesis. In SA-treated adipocytes, while fatty acid synthetase was downregulated, AMP-activated protein kinase (AMPK) was upregulated. Furthermore, SA suppressed body weight and triglyceride content in DIO zebrafish.

CONCLUSION

 SA is a potential therapeutic agent in the management of metabolic disorders, such as obesity.

Application of MS-Based Metabolomic Approaches in Analysis of Starfish and Sea Cucumber Bioactive Compounds

Today, marine natural products are considered one of the main sources of compounds for drug development. Starfish and sea cucumbers are potential sources of natural products of pharmaceutical interest. Among their metabolites, polar steroids, triterpene glycosides, and polar lipids have attracted a great deal of attention; however, studying these compounds by conventional methods is challenging. The application of modern MS-based approaches can help to obtain valuable information about such compounds. This review provides an up-to-date overview of MS-based applications for starfish and sea cucumber bioactive compounds analysis. While describing most characteristic features of MS-based approaches in the context of starfish and sea cucumber metabolites, including sample preparation and MS analysis steps, the present paper mainly focuses on the application of MS-based metabolic profiling of polar steroid compounds, triterpene glycosides, and lipids. The application of MS in metabolomics studies is also outlined.

Characterizations and the Mechanism Underlying Osteogenic Activity of Peptides from Enzymatic Hydrolysates of Stichopus japonicus

Sea cucumber (Stichopus japonicus) is a kind of fishery product with high nutritional value. It exhibits a wide range of biological activity and has potential application in the food, pharmaceutical, and biomedical industries. However, there are no reports available on the effects of S. japonicus peptides (SJP) on bone mineral density regulations. The purpose of this work was to analyze the composition and osteogenic activity of SJP and explore its underlying mechanism. The results showed that SJP stimulated cell proliferation, differentiation, and mineralization in a dose-dependent manner. In addition, SJP could promote the proliferation of MC3T3-E1 cells by altering the cell cycle progression and regulating the expression of Cyclins. Besides, SJP activated the WNT/β-catenin pathway and increased the nuclear level of the active form β-catenin. Furthermore, SJP also induced the expression of bone morphogenetic protein (BMP-2) and increase the phosphorylation levels of p38, JNK, and ERK, suggesting that the osteogenic activity of SJP may be achieved through the activation of WNT/β-catenin and BMP/MAPK signal pathways. In vivo, SJP significantly inhibited the serum levels of RANKL, ALP, and TRAP, whereas it increased the levels of osteocalcin and osteoprotegerin in OVX-mice. These results indicate that SJP may have the potential to stimulate bone formation and regeneration, and may be used as a functional food or nutritional supplement to prevent osteoporosis.

Comprehensive review on signaling pathways of dietary saponins in cancer cells suppression

Nutrigenomics utilizes high-throughput genomic technologies to reveal changes in gene and protein levels. Excitingly, ever-growing body of scientific findings has provided sufficient evidence about the interplay between diet and genes. Cutting-edge research and advancements in genomics, epigenetics and metabolomics have deepened our understanding on the role of dietary factors in the inhibition of carcinogenesis and metastasis. Dietary saponins, a type of triterpene glycosides, are generally found in Platycodon grandifloras, Dioscorea oppositifolia, asparagus, legumes, and sea cucumber. Wealth of information has started to shed light on pleiotropic mechanistic roles of dietary saponins in cancer prevention and inhibition. In this review, we have attempted to summarize the in vitro research of dietary saponins in the last two decades by searching common databases such as Google Scholar, PubMed, Scopus, and Web of Science. The results showed that dietary saponins exerted anti-cancer activities via regulation of apoptosis, autophagy, arrest cell cycle, anti-proliferation, anti-metastasis, and anti-angiogenesis, by regulation of several critical signaling pathways, including MAPK, PI3K/Akt/mTOR, NF-κB, and VEGF/VEGFR. However, there is no data about the dosage of dietary saponins for practical anti-cancer effects in human bodies. Extensive clinical studies are needed to confirm the effectiveness of dietary saponins for further commercial and medical applications.

Effects of microwave vacuum drying on the moisture migration, microstructure, and rehydration of sea cucumber

Effectsof microwave vacuum drying (MVD) on moisture migration, microstructure, and rehydration of sea cucumber were investigated in this paper. Vacuum condition avoided the exposure of sea cucumber to high temperature. Low-field nuclear magnetic resonance relaxation results revealed that the peaks of three water components in sea cucumber shifted to short relaxation time during MVD process, and the peak area of major water component-immobilized water-decreased significantly due to water evaporation. Magnetic resonance imaging found that the water in the internal layer of sea cucumber body wall was first removed due to the internal heating of microwave, and then the water in the outer layer. Higher microwave power could promote the moisture transfer motion during drying process, and shorten the drying time. Porous microstructure was observed by Cryo scanning electronic microscope images in sea cucumber dried with microwave power of 200 and 250 W, which might be responsible for high values of rehydration ratio and water holding capacity. High microwave power caused the increase of amino acids content, but had no significant effect on the change of saponins content. In addition, excellent prediction models of moisture ratio have been developed by partial least squares regression analysis based on transverse relaxation data, which proved the feasibility of low-field nuclear magnetic resonance to monitor moisture changes of sea cucumber during MVD process. PRACTICAL APPLICATION: Effects of microwave vacuum drying (MVD) on moisture migration, microstructure, and rehydration of sea cucumber were investigated. Understanding the impacts of MVD drying on water status, texture, and nutritional characteristics of sea cucumber is important to improve the processing quality of dried sea cucumber.

Multidirectional effects of saponin fraction isolated from the leaves of sea buckthorn Elaeagnus rhamnoides (L.) A. Nelson

Many studies show that saponins isolated from various plants have a cytotoxic effect on cancer cells inducing apoptosis and autophagy. On the other hand, saponins also exhibit a number of beneficial properties, such as antioxidant properties. Thus, saponins can be considered both in terms of their therapeutic and protective effects during anticancer treatment. In this study, we investigated the effect of the saponin fraction isolated from sea buckthorn (Elaeagnus rhamnoides (L.) A. Nelson) leaves on the viability of HL-60 cancer cells using resazurin assay and its ability to induction of apoptosis with Annexin V-FITC and propidium iodide (PI) double staining. Moreover, we studied its effect on the oxidative stress induced by H₂O₂, and anti-platelet and anticoagulant potential in whole blood using T-TAS, a microchip-based flow chamber system. We observed that the saponin fraction significantly decreased the viability of HL-60 cells at the concentration above 50 µg/mL and induced apoptosis at the concentration of 100 µg/mL. Moreover, we observed that saponin fraction used at lower concentrations, such as 0.5 and 1 µg/mL, stimulated HL-60 cells and increased their viability. The saponin fraction also decreased the level of free radicals and reduced oxidative DNA damage measured by the comet assay. However, at high concentration of oxidant H₂O₂ equal 5 mM, we noticed that the saponin fraction at 50 µg/mL increased the level of free radicals in HL-60 cells. We also demonstrated anticoagulant potential of the saponin fraction at the concentration of 50 µg/mL. Our results indicate that the saponin fraction obtained from sea buckthorn leaves can show both chemotherapeutic and chemoprotective potential.

Low Molecular Weight Oligosaccharide from Panax ginseng C.A. Meyer against UV-Mediated Apoptosis and Inhibits Tyrosinase Activity In Vitro and In Vivo

To find new anti-UV and whitening agents, 21 fractions isolated from three preparations of ginseng (white, red, and black ginseng) were screened, and their antioxidant effects on AAPH- or H₂O₂-induced damage were investigated. Furthermore, the protective effect against UV-mediated apoptosis and the tyrosinase inhibitory activity of the targeted fractions were evaluated in vitro and in a zebrafish model. Among all fractions, F10 from white ginseng was selected as having the strongest anti-UV and antimelanogenesis activities. This fraction exhibited excellent inhibitory effects on the pigmentation of zebrafish, which may be due to its potential tyrosinase inhibitory activity. Additionally, the chemical composition of F10 was evaluated by UPLC-MS and NMR instruments. The results indicated that F10 had a carbohydrate content of more than 76%, and the weight-average molecular weight was approximately 239 Da. Disaccharide sucrose was the main active compound in F10. These results suggest that F10 could be used as an ingredient for whitening cosmetics and regarded as an anti-UV filter in the future.

Fucoxanthin-rich fraction from Sargassum fusiformis alleviates particulate matter-induced inflammation in vitro and in vivo

Particulate matter (PM) contributes to air pollution and primarily originates from unregulated industrial emissions and seasonal natural dust emissions. Fucoxanthin (Fx) is a marine natural pigment from brown macroalgae that has been shown to have various beneficial effects on health. However, the effects of Fx on PM-induced toxicities in cells and animals have not been assessed. In this study, we investigated the anti-inflammatory potential of the Fx-rich fraction (FxRF) of Sargassum fusiformis against PM-mediated inflammatory responses. The FxRF composition was analyzed by rapid-resolution liquid chromatography mass spectrometry. Fx and other main pigments were identified. FxRF attenuated the production of inflammatory components, including prostaglandin E2 (PGE2), cyclooxygenase-2, interleukin (IL)-1β, and IL-6 from PM-exposed HaCaT keratinocytes. PM exposure also reduced the levels of nitric oxide (NO), tumor necrosis factor-α, inducible nitric oxide synthase (iNOS), and PGE2 in PM-exposed RAW264.7 macrophages. Additionally, the culture medium from PM-exposed HaCaT cells induced upregulation of NO, iNOS, PGE2, and pro-inflammatory cytokines in RAW264.7 macrophages. FxRF also significantly decreased the expression levels of factors involved in inflammatory responses, such as NO, reactive oxygen species, and cell death, in PM-exposed zebrafish embryos. These results demonstrated the potential protective effects of FxRF against PM-induced inflammation both in vitro and in a zebrafish model.