Antitumor activity and underlying mechanism of Sargassum fusiforme polysaccharides in CNE-bearing mice

Near-infrared spectroscopy for the quality control of Sarassum fusiforme: Prediction of antioxidant capability of Sarassum fusiforme at different growth stages

The healthy benefits of seaweed have increased its market demand in recent times. Quality control is crucial for seaweed to ensure the customers' interest and the sustainable development of seaweed farming industry. This study developed a quality control method for seaweed Sargassum fusiforme, rapid and simple, using near-infrared spectroscopy (NIR) and chemometrics for the prediction of antioxidant capacity of S. fusiforme from different growth stages, S. fusiforme was distinguished according to growth stage by partial least squares-discriminant analysis (PLS-DA) and particle swarm optimization-support vector machine (PSO-SVM). The antioxidant properties including 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) scavenging capacity, 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging capacity, and ferric reducing antioxidant power (FRAP) were quantified using competitive adaptive reweighted sampling (CARS)-PLS model. Based on the spectra data preprocessed by multiplicative scatter and standard normal variate methods, the PSO-SVM models can accurately identify the growth stage of all S. fusiforme samples. The CARS-PLS models exhibited good performance in predicting the antioxidant capacity of S. fusiforme, with coefficient of determination (RP2) and root mean square error (RMSEP) values in the independent prediction sets reaching 0.9778 and 0.4018 % for ABTS, 0.9414 and 2.0795 % for DPPH, and 0.9763 and 2.4386 μmol L-1 for FRAP, respectively. The quality and market price of S. fusiforme should increase in the order of maturation < growth < seedling regarding the antioxidant property. The overall results indicated that the NIR spectroscopy accompanied by chemometrics can assist for the quality control of S. fusiforme in a more rapid and simple manner. This study also provided a customer-oriented concept of seaweed quality grading based on deep insight into the antioxidant capability of S. fusiforme at different growth stages, which is highly valuable for precise quality control and standardization of seaweed market.

Bioactivities of the Popular Edible Brown Seaweed Sargassum fusiforme: A Review

Sargassum fusiforme has a wide range of active constituents (such as polysaccharides, sterols, polyphenols, terpenes, amino acids, trace elements, etc.) and is an economically important brown algae with a long history. In recent years, S. fusiforme has been intensively studied and has attracted wide attention in the fields of agriculture, environment, medicine, and functional food. In this review, we reviewed the current research status of S. fusiforme at home and abroad over the past decade by searching Web of science, Google Scholar, and other databases, and structurally analyzed the active components of S. fusiforme, and on this basis, we focused on summarizing the cutting-edge research and scientific issues on the role of various active substances in S. fusiforme in exerting antioxidant, anti-inflammatory, antitumor, antidiabetic, immunomodulatory, antiviral antibacterial, and anticoagulant effects. The mechanisms by which different substances exert active effects were further summarized by exploring different experimental models and are shown visually. It provides a reference to promote further development and comprehensive utilization of S. fusiforme resources.

Hypolipidemic Activity and Mechanism of Action of Sargassum fusiforme Polysaccharides

Sargassum fusiforme polysaccharide (SFP) is a kind of biologically active macromolecule with biological functions. In this study, oxidative stress and high-fat HepG2 cell models were established to investigate its lipid-lowering activity and mechanism of action. It was found that SFP and its two isolated fractions had antioxidant effects on the cells. It was also found the polysaccharides decreased the content of total cholesterol and total triglyceride in the high-fat cells. RT-qPCR assays revealed that the three polysaccharides down-regulated the mRNA expression level of ACC, PPARγ, and SREBP-2. It could be concluded that the hypolipidemic effect of SFPs is achieved via multiple pathways, including the regulation on the expression level of lipid metabolism-related key enzymes and factors, and binding with bile acids. The hypolipidemic effect of SFPs could be partially due to their antioxidant activity. SFPs developed in the present work have potential as ingredients of functional foods with hypolipidemic effect.

Triterpenoids of Ganoderma lucidum inhibited S180 sarcoma and H22 hepatoma in mice by regulating gut microbiota

In order to explore effect of natural plant extracts on anti-tumor and prevent tumor development. The study assessed the antitumor effect of triterpenoids of Ganoderma lucidum (TGL) on S180 and H22 tumor bearing mice. A triterpene compound, 2α, 3α, 23-trihydroxy-urs-12-en-28-oic acid, was successfully isolated and purified from G. lucidum. S180 and H22 cells were subcutaneously inoculated in the left axilla of mice to establish a transplantable tumor model. After, the mice were orally treated with TGL and evaluated by tumor inhibition rate, organ index, and the serum index. The Bax and Bcl-2 proteins and gut microbiota was analyzed using western blot and 16S rDNA sequencing respectively. The results showed the tumor inhibition rates of TGL were higher than 40% in H22 and S180 tumor bearing mice. TGL had a protective effect on the spleen and thymus, and improved lipid peroxidation caused by the increased free radicals. TGL downregulated Bcl-2 and upregulated Bax. In particular, TGL treatment improved the reduction of gut microbiota richness and structure.

Polysaccharide-Based Stimulus-Responsive Nanomedicines for Combination Cancer Immunotherapy

Cancer immunotherapy is a promising antitumor approach, whereas nontherapeutic side effects, tumor microenvironment (TME) intricacy, and low tumor immunogenicity limit its therapeutic efficacy. In recent years, combination immunotherapy with other therapies has been proven to considerably increase antitumor efficacy. However, achieving codelivery of the drugs to the tumor site remains a major challenge. Stimulus-responsive nanodelivery systems show controlled drug delivery and precise drug release. Polysaccharides, a family of potential biomaterials, are widely used in the development of stimulus-responsive nanomedicines due to their unique physicochemical properties, biocompatibility, and modifiability. Here, the antitumor activity of polysaccharides and several combined immunotherapy strategies (e.g., immunotherapy combined with chemotherapy, photodynamic therapy, or photothermal therapy) are summarized. More importantly, the recent progress of polysaccharide-based stimulus-responsive nanomedicines for combination cancer immunotherapy is discussed, with the focus on construction of nanomedicine, targeted delivery, drug release, and enhanced antitumor effects. Finally, the limitations and application prospects of this new field are discussed.

Anti-Leukemia Activity of Polysaccharide from Sargassum fusiforme via the PI3K/AKT/BAD Pathway In Vivo and In Vitro

Studies have shown that Sargassum fusiforme and its extracts are effective herbal treatments for leukemia. We previously found that a polysaccharide from Sargassum fusiforme, SFP 2205, stimulated apoptosis in human erythroleukemia (HEL) cells. However, the structural characterization and antitumoral mechanisms of SFP 2205 remain uncertain. Here, we studied the structural characteristics and anticancer mechanisms of SFP 2205 in HEL cells and a xenograft mouse model. The results demonstrated that SFP 2205, with a molecular weight of 41.85 kDa, consists of mannose, rhamnose, galactose, xylose, glucose, and fucose with monosaccharides composition of 14.2%, 9.4%, 11.8%, 13.7%, 11.0%, and 38.3%, respectively. On animal assays, SFP 2205 significantly inhibited growth of HEL tumor xenografts with no discernible toxicity to normal tissues. Western blotting showed that SFP 2205 therapy improved Bad, Caspase-9, and Caspase-3 protein expression, and ultimately induced HEL tumor apoptosis, indicating mitochondrial pathway involvement. Furthermore, SFP 2205 blocked the PI3K/AKT signaling pathway and 740 Y-P, an activator of the PI3K/AKT pathway, rescued the effects of SFP 2205 on HEL cell proliferation and apoptosis. Overall, SFP 2205 may be a potential functional food additive or adjuvant for preventing or treating leukemia.

Preparation of Water-Soluble Acetylaminoglucan with Low Molecular Weight and Its Anti-Tumor Activity on H22 Tumor-Bearing Mice

In this study, a novel low molecular weight of acetylaminoglucan (AGA) was obtained and its antitumor activity on H22 tumor-bearing mice was investigated. The results of UV, HPLC and FT-IR showed that AGA present high purity with low molecular weight of 2.76 × 103 Da. Animal experiments showed that AGA could inhibit the proliferation of tumor cells in H22 tumor-bearing mice by protecting the immune organs, enhancing the phagocytosis ability of macrophages, killing activity of NK cells and proliferation capacity of lymphocytes, improving the levels of cytokines in vivo and regulating the distribution of lymphocyte subsets, and the tumor inhibition rate reached to 52.74% (50 mg/kg). Cell cycle determination further indicated that AGA could induce apoptosis of tumor cells and arrests it in S phase. These results will provide a data basis for the potential application of AGA in pharmaceutical industry.

Comparison on Bioactivities and Characteristics of Polysaccharides From Four Varieties of Gastrodia elata Blume

The composition, physicochemical properties, in vitro biological activity, and hypoglycemic activity exhibited by polysaccharides from four varieties of G. elata were investigated in this study; the four extracted GaE polysaccharides were termed as GaE-B (G. elata Bl. f. glauca S. chow polysaccharides), GaE-R (G. elata Bl. f. elata polysaccharides), GaE-Hyb (hybridization of G. elata Bl. f. glauca S. chow and G. elata Bl. f. elata polysaccharides), and GaE-G (G. elata Bl. f. viridis Makino polysaccharides). As revealed by the results, the GaE polysaccharides were found with the same monosaccharide composition, primarily including glucose, whereas the content of each variety was significantly different. In addition, different degrees of differences were found in the in vitro antioxidant and hypoglycemic activity, molecular weight, yield, and chemical composition exhibited by the abovementioned varieties. However, GaE-B and GaE-Hyb were found with similar physical properties, chemical composition, and antioxidant and hypoglycemic activity. GaE-R had the lowest yield, total sugar content, and molecular weight, whereas it involved higher xylose, binding protein, and polyphenols as well as higher antioxidant and hypoglycemic activity. In contrast, GaE-G was found with the highest yield, total sugar content, and molecular weight, whereas it contained the lowest xylose, binding protein, and polyphenols, as well as the weakest antioxidant and hypoglycemic activity. In brief, the polysaccharide of G. elata, a plant resource for homology of medicine and food, could more significantly enhance the biological activity of G. elata as it was released in the process of decocting and stewing. To be specific, the assessment of polysaccharide activity alone suggested that GaE-R was the best.

Comparative study on the structural characterization and α-glucosidase inhibitory activity of polysaccharide fractions extracted from Sargassum fusiforme at different pH conditions

Sargassum fusiforme polysaccharides (SFPs), including SFP-3-40, SFP-3-60, SFP-3-80, SFP-7-40, SFP-7-60, SFP-7-80, SFP-10-40, SFP-10-60, and SFP-10-80, were extracted at different pH (3, 7, and 10), and then precipitated with graded precipitation of 40%, 60% and 80% (v/v) ethanol solution, respectively. Their physicochemical properties and α-glucosidase inhibitory activity were determined. Results showed that SFPs significantly differed in the contents of total sugar, protein, uronic acid, sulfate, the zeta potential, and molecular weight distribution. SFPs, including SFP-10-40, SFP-10-60, and SFP-10-80, had bigger absolute zeta potential value and higher respective average molecular weight in the same ethanol concentration precipitate. All samples were mainly composed of fucose, glucuronic acid, and mannose with different molar ratios. The extraction pH and precipitation ethanol solution concentration caused little changes in functional groups, but significantly altered surface morphology of SFPs. Congo red test revealed that all polysaccharides were not helical polysaccharides. Rheological measurements indicated that SFPs were pseudoplastic fluids and showed elastic behavior of the gel. Except SFP-3-40 and SFP-3-60, all other samples had a stronger α-glucosidase inhibitory activity than that of acarbose. The inhibition type of SFPs against α-glucosidase varied owing to different extraction pH and precipitation ethyl concentration. This study shows that extraction pH can significantly affect the structure and hypoglycemic activity of SFPs and provide a data support for the scientific use of Sargassum fusiforme in industrial production.

Chemical Characterization, Antitumor, and Immune-Enhancing Activities of Polysaccharide from Sargassum pallidum

Searching for natural products with antitumor and immune-enhancing activities is an important aspect of cancer research. Sargassum pallidum is an edible brown alga that has been used in Chinese traditional medicine for the treatment of tumors. However, the purification and application of its active components are still insufficient. In the present study, the polysaccharides from S. pallidum (SPPs) with antitumor and immune-enhancing activities were isolated and purified, and five polysaccharide fractions (SPP-0.3, SPP-0.5, SPP-0.7, SPP-1, and SPP-2) were obtained. The ratio of total saccharides, monosaccharide composition, and sulfated contents was determined, and their structures were analyzed by Fourier transform infrared spectroscopy. Moreover, bioactivity analysis showed that all five fractions had significant antitumor activity against three types of cancer cells (A549, HepG2, and B16), and can induce cancer cell apoptosis. In addition, the results indicated that SPPs can enhance the proliferation of immune cells and improve the expression levels of serum cytokines (IL-6, IL-1β, iNOS, and TNF-α). SPP-0.7 was identified as the most active fraction and selected for further purification, and its physicochemical properties and antitumor mechanism were further analyzed. Transcriptome sequencing result showed that SPP-0.7 can significantly induce the cell apoptosis, cytokine secretion, and cellular stress response process, and inhibit the normal physiological processes of cancer cells. Overall, SPPs and SPP-0.7 may be suitable for use as potential candidate agents for cancer therapy.

Effects of simulated digestion in vitro on the structure and macrophages activation of fucoidan from Sargassum fusiforme

Molecular size and spatial structure affect the bioactivities of polysaccharides. SFF is a fucoidan extracted from Sargassum fusiforme. The possible changes of SFF affected by gastrointestinal tract and subsequently changes of its physicochemical property or its bioactivity have yet to be systematically investigated. Our results showed that DSFF, the gastrointestinal digestion product of SFF, has increased reducing sugar content, increased proportion of low molecular weight components, and a more clustered island-like morphology. Both SFF and DSFF activate RAW 264.7 macrophages evidenced by the increasing level of NO, intracellular ROS, and macrophages cytokines. Further investigation showed that DSFF induced M1 phenotype polarization in RAW 264.7 cells. DSFF also showed stronger macrophage activation and phenotype polarization than SFF. Our present work showed that SFF could be digested by simulated gastrointestinal environment in vitro and the digested product DSFF showed higher efficiency in macrophages activation and phenotype polarization.

Brown Seaweed Food Supplementation: Effects on Allergy and Inflammation and Its Consequences

Multiple health benefits have been ascribed to brown seaweeds that are used traditionally as dietary component mostly in Asia. This systematic review summarizes information on the impact of brown seaweeds or components on inflammation, and inflammation-related pathologies, such as allergies, diabetes mellitus and obesity. We focus on oral supplementation thus intending the use of brown seaweeds as food additives. Despite the great diversity of experimental systems in which distinct species and compounds were tested for their effects on inflammation and immunity, a remarkably homogeneous picture arises. The predominant effects of consumption of brown seaweeds or compounds can be classified into three categories: (1) inhibition of reactive oxygen species, known to be important drivers of inflammation; (2) regulation, i.e., in most cases inhibition of proinflammatory NF-κB signaling; (3) modulation of adaptive immune responses, in particular by interfering with T-helper cell polarization. Over the last decades, several inflammation-related diseases have increased substantially. These include allergies and autoimmune diseases as well as morbidities associated with lifestyle and aging. In this light, further development of brown seaweeds and seaweed compounds as functional foods and nutriceuticals might contribute to combat these challenges.

Could partial nonstarch polysaccharides ameliorate cancer by altering m6A RNA methylation in hosts through intestinal microbiota?

There is a growing scientific view that the improvement of cancer by nonstarch polysaccharides (NSPs) is mediated by intestinal microbiota. Intestinal bacteria affect the supply of methyl donor substances and influence N⁶-methyladenosine (m⁶A) RNA methylation. As one of the epigenetic/epitranscriptomic modifications, m⁶A RNA methylation is closely related to the initiation and progression of cancers. This review summarizes the cancer-improving effects of NSPs through modulation of intestinal microbiota. It also summarizes the relationship between intestinal bacteria and the supply of methyl donor substances. Moreover, it also provides a summary of the effects of m⁶A RNA methylation on various types of cancer. The proposed mechanism is that, dietary consumed NSPs are utilized by specific intestinal bacteria and further reshape the microbial structure. Methyl donor substances will be directly or indirectly generated by the reshaped-microbiota, and affect the m⁶A RNA methylation of cancer-related and pro-carcinogenic inflammatory cytokine genes. Therefore, NSPs may change the m⁶A RNA methylation by affecting the methyl donor supply produced by intestinal microbiota and ameliorate cancer. This review discussed the possibility of cancer improvement of bioactive NSPs achieved by impacting RNA methylation via the intestinal microbiota, and it will offer new insights for the application of NSPs toward specific cancer prevention.

Structural Characterization of an Alkali-Soluble Polysaccharide from Angelica sinensis and Its Antitumor Activity in Vivo

A novel alkali-soluble polysaccharide (AASP) was isolated from Angelica sinensis (Oliv.) Diels under aqueous alkali treatment, and its structural characterization and antitumor activity in Vivo were evaluated in present study. Results of HPGPC and IC revealed that AASP was a neutral polysaccharide containing Ara, Gal and Glc in the mole ratio of 1.00 : 2.26 : 24.43, with the average molecular weight of 4.7 kDa. Periodate oxidation, Smith degradation, methylation, FT-IR, and NMR analyses further demonstrated that a preliminary structure of AASP was proposed as follows: (1→3)-linked arabinose, (1→6)-linked galactose, and (1→), (1→4), (1→6), (1→3,6)-linked glucose with α- and β-configuration. In Vivo antitumor assays, AASP exhibited prominent antitumor effects on H22 hepatoma cells with an inhibitory ratio of 48.57 % and effectively protected thymuses and spleens of tumor-bearing mice. Besides, AASP displayed a proliferation stimulating activity of immunocytes (splenocytes, peritoneal macrophages and natural killer cells), and an auxo-action for cytokines release (TNF-α, IL-2 and IFN-γ), leading to the apoptosis of H22 solid tumors cells via G0/G1 phase arrested. The above data demonstrated that AASP holds great application potential to be a safe and effective antitumor supplement in the future.

In vitro fermentation characteristics of polysaccharide from Sargassum fusiforme and its modulation effects on gut microbiota

In this study, polysaccharides from Sargassum fusiforme (SFP) were obtained by cellulase assisted hot water extraction. The chemical composition, structural characteristics, and in vitro fermentation properties of SFP were investigated. Results showed that the contents of total carbohydrate, protein, uronic acid and sulfate in SFP were 83.25%, 1.42%, 12.80% and 7.81%, respectively. It mainly consisted of fucose glucose and galactose, with molecular weight of 255.83 kDa. UV spectrum, FTIR, SEM and AFM results showed that SFP was a typical sulfate polysaccharide with relative smooth surface and regular shape. After in vitro fermentation for 24 h, the pH value of fermentation medium declined significantly (p < 0.05), utilization of carbohydrate was 53.17%. The contents of total SCFAs increased by 10.77 times. Moreover, SFP fermentation could change obviously the microbiota composition. It significantly increased the abundance of Faecalibacterium (increased by 49.07% compared with the Blank24 group), Phascolarctobacterium (increased by 88.06%), Bifidobacterium (increased by 139.13%), Ruminococcaceae_UCG-014 (increased by 177.78%), and Lactobacillus (increased by 400.00%), decreased the abundance of Prevotella_9 (decreased by 34.54%) and Blautia (decreased by 40.79%) at genus level. These results showed that SFP could be utilized by microbiota in human feces, and may have the potential to improve intestinal health.

Inhibition of glucuronomannan hexamer on the proliferation of lung cancer through binding with immunoglobulin G

The anti-lung cancer activity of oligosaccharides derived from glucuronomannan was investigated. The inhibition of A549 cell proliferation by glucuronomannan (Gn) and its oligomers (dimer (G2), tetramer (G4) and hexamer (G6)) were concentration dependent. In vivo activities on the A549-derived tumor xenografts showed the tumor inhibition of G2, G4 and G6 were 17 %, 40 % and 46 %, respectively. Organ coefficients in nude mice showed an increase in the kidney with G4, the brain with G6, and the spleen with G6. An advanced tandem mass tag labeled proteomics approach was performed. A significant differential expression was found in 59 out of the 4371 proteins, which involved the immune system. Surface plasmon resonance (SPR) studies revealed G6 was strongly bound to immunoglobulin G. This suggests that glucuronomannan hexamer inhibits the proliferation of lung cancer through its binding to immunoglobulin.

Structural characterization and anti-lung cancer activity of a sulfated glucurono-xylo-rhamnan from Enteromorpha prolifera

A sulfated glucurono-xylo-rhamnan (EP-3-H) was purified from a green alga, Enteromorpha prolifera. EP-3-H and its oligomers were characterized by high performance liquid chromatography, mass spectrometry and one and two-dimensional nuclear magnetic resource spectroscopy. The structural analysis showed EP-3-H has a backbone of glucurono-xylo-rhamnan, branches with glucuronic acid and sulfated at C3 of rhamnose and/or C2 of xylose. The inhibition of EP-3-H on human lung cancer A549 cell proliferation in vitro and its therapeutic effects in BALB/c-nu mice in vivo were determined to evaluate the anti-lung cancer activity of EP-3-H. The tumor inhibition level was 59 %, suggesting that EP-3-H might be a good candidate for the treatment of lung cancer. Surface plasmon resonance (SPR) studies revealed the IC₅₀ on the binding of fibroblast growth factors, (FGF1 and FGF2), to heparin were 0.85 and 1.47 mg/mL, respectively. These results suggest that EP-3-H inhibits cancer proliferation by interacting with these growth factors.

A comparison of a polysaccharide extracted from ginger (Zingiber officinale) stems and leaves using different methods: preparation, structure characteristics, and biological activities

This study investigates how extraction method impacts the yield, chemical composition, structure characteristics, hypoglycemic and antioxidant activity of polysaccharides from ginger (Zingiber officinale Roscoe) stems and leaves (GSLP). Four extraction methods were employed to obtain the GSLP, including hot water extraction (HWE), ultrasound-assisted extraction (UAE), alkaline solution extraction (ASE), and enzyme-assisted extraction (EAE). The data showed that ASE produced highest extraction yield compared to the other extraction methods. Scanning electron microscopy indicated that GSLP microstructures were greatly influenced by extraction method. Moreover, in vitro hypoglycemic activity and antioxidant activity experiments demonstrated that the biological capacities of ASE-GSLP were superior to GSLPs extracted by the other methods. Taken together, these results indicate that polysaccharides from ginger stems and leaves obtained by alkali, complex enzyme, and ultrasonic-assisted extractions are imbued with different characteristic mechanisms of degradation, despite the uniformity of their main structures. In addition, ASE-GSLP displayed better biological activities probably due to its abundant uronic acid content, higher sulfate radical, and smaller molecular weight. Thus, it can be concluded that ASE has great potential as an effective strategy for obtaining polysaccharides from stems and leaves because of its higher yield and the remarkable bioactivity of its products.

Antipyretic and antitumor effects of a purified polysaccharide from aerial parts of Tetrastigma hemsleyanum

ETHNOPHARMACOLOGICAL RELEVANCE

Tetrastigma hemsleyanum Diels et Gilg (Sanyeqing) is traditionally used as a folk medicine for the treatments of inflammation, high fever, hepatitis and cancer, and can improve the immune function of the patient. It belongs to the family of Vitaceae, and is mainly distributed in southeast China (Yunnan province) and can be found in India (Andaman Islands), Myanmar, Thailand, Vietnam, Malaysia and Indonesia in the valleys with 1100-1300 m above the sea level.

AIM OF THE STUDY

The present study aimed to characterize the chemical properties of a purified polysaccharide extracted from the aerial part of Tetrastigma hemsleyanum (SYQP) and investigate its antipyretic and antitumor effects in mice models.

MATERIALS AND METHODS

Water-soluble crude polysaccharides from the aerial parts of Tetrastigma hemsleyanum were extracted and fractionated by DEAE and gel permeation chromatography. Homogeneity, molecular weight, monosaccharide composition, and FTIR analysis were performed to characterize the SYQP. Antipyretic effect of SYQP was examined using Brewer's yeast induced hyperthermia test. Antitumor effect was investigated using H22 tumor bearing mice. The serum cytokines were determined to evaluated the biological activities of SYQP.

RESULTS

SYQP was composed of galacturonic acid (GalA), glucose (Glc), mannose (Man), arabinose (Ara), galactose (Gal), and rhamnose (Rha) with a molar ratio of 11.3:7.1:2.5:1.0:0.9:0.5 and it had an average molecular weight of 66.2 kDa. The oral administration of SYQP at 200 and 400 mg/kg could markedly suppress the hyperthermia of mice induced by Brewer's yeast and decrease the production of cytokines especially prostaglandin E2 (PGE2) in the serum of mice. SYQP inhibited the growth of H22 tumor in mice with inhibitory rate of 39.9% at the administration dose of 200 mg/kg and increased the production of cytokines such as tumor necrosis factor-alpha (TNF-a) and interferon γ (IFN-γ). Experimental results showed that the preventive administration of SYQP before lipopolysaccharide (LPS) reduced the high cytokine levels such as IL-6, IL-10 and IFN-γ, indicating that SYQP might act as a competitor with LPS to interact with toll like receptor 4 (TLR4), which further regulated the secretion of cytokines.

CONCLUSION

The anti-inflammatory and antitumor activities of SYQP might be related to its regulation of host immune function by controlling the secretion of cytokines.

A novel polysaccharide from Castanea mollissima Blume: Preparation, characteristics and antitumor activities in vitro and in vivo

A new water-soluble polysaccharide, CMP90, with a molecular weight of 23.9 kDa was isolated from Castanea mollissima Blume and the preliminary structural characteristics and antitumor effects of CMP90 in vitro and in vivo were investigated in the research. CMP90 consists of arabinose, galactose, glucose, xylose and mannose (molar ratio: 0.08:0.11:5.14:0.12:0.08) with α- and β-anomeric units. The results of in vitro experiments indicated that CMP90 exhibited a significant inhibitory effect on the proliferation of HL-60 cells with typical apoptotic characteristics by inducing cell cycle arrested at G1/M phase. Additionally, the results in vivo suggested CMP90 was able to inhibit the growth of S180 solid tumors via protecting immune organs, improving the levels of serum cytokines (TNF-α, IL-2 and IFN-γ), enhancing the activities of immune cells (macrophages, lymphocytes and NK cells) and inducing cell apoptosis or death. Taken together, these combined data clearly indicated that CMP90 may be used as a potential candidate agent for cancer therapy.

Structural analysis of a novel sulfated galacto-fuco-xylo-glucurono-mannan from Sargassum fusiforme and its anti-lung cancer activity

Polysaccharide (HFSGF) was purified from Sargassum fusiforme. Autohydrolysis and gel column chromatography were performed to fractionate HFSGF into three components (HFSGF-S, HFSGF-L and HFSGF-H). Compositional analysis, mass spectrometry and nuclear magnetic resonance spectroscopy were used to elucidate the structural features of HFSGF. HFSGF-S was a mixture of sulfated galacto-fuco-oligomers, from the branches terminal ends; in HFSGF-L, the branches of HFSGF, was a sulfated galactofucan, containing a backbone of 1,3-linked α-L-fucan sulfated at C2/4 and/or C4 and interspersed with galactose (Gal); and in HFSGF-H, the backbone of HFSGF, was composed of alternating 1,2-linked α-D-mannose (Man) and 1,4-linked β-D-glucuronic acid (GlcA), branched with sulfated galactofucan or sulfated fucan, 1,3-linked α-L-fucan sulfated at C2/4 and/or C4 and partly interspersed with Gal. Some fucose (Fuc) residues were also partially branched with xylose (Xyl). The anti-lung cancer activities of HFSGF-L and HFSGF-H against human lung cancer A549 cells in vitro and A549 xenograft tumor growth in vivo were determined. HFSGF-H had higher activity in vitro (IC50 ~12 mg/mL for 24 h) and in vivo (tumor inhibition ~51%.) than HFSGF-L, indicating that HFSGF-H might be a leading compound for a potential new therapeutics for the treatment of lung cancer.

Composition, isolation, purification and biological activities of Sargassum fusiforme polysaccharides: A review

Sargassum fusiforme polysaccharides, acidic water-soluble polysaccharides extract from Sargassum fusiforme, are mainly composed of alginic acid, fucoidan and laminaran. Alginic acid is carboxyl-containing polysaccharide formed by joining β-D-mannuronic acid and α-L-guluronic acid through β-(1→4)/α-(1→4) glycosidic bond. Fucoidan, a natural water-soluble sulfated heteropolysaccharide with fucose and sulfuric acid groups as the core structure, is mainly linked by L-fucose through α-(1→3) glycosidic bond and has the strongest biological activity. Laminaran is mainly composed of β-D-glucose through β-(1→3) glycosidic bond linkage. Sargassum fusiforme polysaccharides have a variety of pharmacological activities, including antioxidant, anti-tumor, promoting immunity, anti-aging, prompting bone growth, lowering blood glucose, anti-coagulation, anti-virus, anti-bacteria, anti-fatigue, promoting growth and development, and skin protection. These activities are closely related to the functions of fucoidan in Sargassum fusiforme polysaccharides, which fucoidan is able to strengthen immune system and antioxidation in human body. In this review, the composition, the isolation and purification, and the biological activities of Sargassum fusiforme polysaccharides are discussed and can bereference for further study.

Characterization and anti-tumor bioactivity of astragalus polysaccharides by immunomodulation

Astragalus polysaccharide (APS) has attracted growing interests in the field of anti-cancer by direct killing effect and improving immune function. In this study, the structure and composition of APS was determined, following the evaluation of in vitro and in vivo anti-tumor activity of APS targeted macrophages and host immune system based on immunoregulated strategy. The results indicated that APS had no direct cytotoxicity against 4T1 cells, but APS mediated macrophages could significantly inhibit the growth of 4T1 cells by the induction of cell cycle arrest (G2 phase) and cell apoptosis. APS mediated macrophages promoted the apoptosis of 4T1 cells mainly through the mitochondrial apoptosis pathway. The in vivo findings demonstrated that APS could markedly improve the thymus index and spleen index, and restore the structure of the damaged thymus and spleen tissue. APS could significantly enhance the proliferation of spleen lymphocytes and increase phagocytosis of peritoneal macrophages in mice. Furthermore, APS was capable of up-regulating the expression of IL-2, TNF-α and IFN-γ in peripheral blood. APS combined with 5-FU could improve the anti-tumor effect accompanied by the immunosuppressive alleviation of 5-FU on immune system, which may be suitable as an immune adjuvant for chemotherapy.

The antiviral property of Sargassum fusiforme polysaccharide for avian leukosis virus subgroup J in vitro and in vivo

Avian Leukosis Virus Subgroup J (ALV-J) is an oncogenic retrovirus, mainly spread by vertical and horizontal transmission, which have caused severe losses in world poultry industry. Sargassum fusiforme polysaccharide (SFP), a marine algae sulfated polysaccharide, has attracted more attention due to its variously biological activities. In this study, the anti-ALV-J property of SFP was assessed in vivo and in vitro. The results demonstrated that different Mw of SFPs showed virustatic activity to ALV-J in vitro by combining with the virus when ALV-J adsorbed onto the host cells. When treated with SFPs, the ALV-J gene and protein expression reduced clearly and SFP-3 (Molecular weight 9 kDa) had the best antiviral effect. Results in vivo showed that the immunosuppression of the ALV-J infected chickens were relieved by SFP-3. Moreover, SFP-3 obviously inhibit the viral shedding and alleviated the organs damage caused by ALV-J. This study offered a new method for ALV-J treatment and enriched the potential application of SFP.

Physicochemical characterization of Sargassum fusiforme fucoidan fractions and their antagonistic effect against P-selectin-mediated cell adhesion

P-selectin, mediated adhesion between endothelium and neutrophils, is a promising target for the therapeutics of acute inflammatory-related diseases. It is reported that brown algal fucoidans can antagonize P-selectin function. However, the fractionation and physicochemical characterization of Sargassum fusiforme fucoidan, and the screening of fucoidan fractions with P-selectin antagonistic capability have not been investigated. In this study, we isolated and fractionated systematically the S. fusiforme fucoidan by ion-exchange chromatography and size exclusion chromatography to obtain eight fucoidan fractions. Their physicochemical characterization was determined by chemical methods, HPLC and FT-IR. The inhibitory capacity of the fucoidan fractions in P-selectin-mediated leukocyte adhesion was evaluated by static adhesion assay and parallel-plate flow chamber. Results showed that fucoidan fractions possessed distinct physicochemical properties, including total carbohydrate, uronic acid and sulfate contents, molecular weight, and monosaccharide compositions. Among all the fucoidan fractions, SFF-32 and SFF-42 showed better blocking ability against P-selectin-mediated cell adhesion.

Comparison of different extraction methods for polysaccharides from bamboo shoots (Chimonobambusa quadrangularis) processing by-products

The aim of this study was to evaluate the influences of extraction methods on the yield, chemical structure and antioxidant activity of polysaccharides from bamboo shoots (Chimonobambusa quadrangularis) processing by-products (CPS). CPSs were extracted by using five methods including hot water extraction (HWE), accelerated solvent extraction (ASE), ultrasonic-assisted extraction (UAE), microwave-assisted extraction (MAE) and enzyme-assisted extraction (EAE). The experimental results showed that the uronic acid contents, monosaccharide contents, molecular weights and antioxidant activities of the five CPSs were significantly different. CPS extracted using ASE method (ASE-CPS) possessed the highest extraction yield (9.94%), the highest medium-high-molecular-weight value (136.07 kDa) and notable antioxidant ability. UAE-CPS had the highest uronic acid (9.42%) and the lowest medium-high-molecular weight value (117.49 kDa), and its antioxidant activity was the best. Based on the correlation analysis, the higher uronic acid content, smaller molecular weight, and lower content of monosaccharide composition of glucose for the CPS-UAE might contribute to its higher antioxidant activity. From an industrial viewpoint, ASE technique could be a promising and alternative way to extract CPS due to its high yield, notable antioxidant activity, and convenient industrialization.

Antineoplastic effect of pectic polysaccharides from green sweet pepper (Capsicum annuum) on mammary tumor cells in vivo and in vitro

The present study investigated the antineoplastic effects of pectic polysaccharides that were extracted from green sweet pepper (Capsicum annuum [CAP]) in the Ehrlich carcinoma in mice and in human mammary tumor lineages. After the subcutaneous inoculation of 2 × 10⁶ Ehrlich tumor cells, Female Swiss mice received 50, 100, or 150 mg/kg CAP or vehicle orally once daily or methotrexate (2.5 mg/kg, i.p., every 5 days) for 21 days. CAP dose-dependently reduced Ehrlich tumor growth. It also reduced the viability of MCF-7, MDA-MB-231, and MDA-MB-436 human mammary cell lineages. Treatment with CAP reduced the gene expression of vascular endothelial growth factor in vivo and in vitro, reduced vessel areas of the tumors, and induced necrosis in Ehrlich solid tumors. CAP treatment significantly increased Interleukin-6 in tumors. The antineoplastic effect of CAP appears to depend on the regulation of inflammation and angiogenesis. Further studies are encouraged to better understand the CAP potential for the treatment of breast tumors.

Beneficial Effect of Intestinal Fermentation of Natural Polysaccharides

With the rapid development of modern society, many chronic diseases are increasing including diabetes, obesity, cardiovascular diseases, etc., which further cause an increased death rate worldwide. A high caloric diet with reduced natural polysaccharides, typically indigestible polysaccharides, is considered a health risk factor. With solid evidence accumulating that indigestible polysaccharides can effectively prevent and/or ameliorate symptoms of many chronic diseases, we give a narrative review of many natural polysaccharides extracted from various food resources which mainly contribute their health beneficial functions via intestinal fermentation.