Structural characterization and antioxidant activity in vitro of polysaccharides from angelica and astragalus

Chemical characterization and pharmacological properties of polysaccharides from Allium roseum leaves: In vitro and in vivo assays

Allium roseum is amongst the most important wild medicinal plants. It is known for its diverse biological properties, including antioxidant, antibacterial and antidiabetic activities. In this work, the polysaccharides (PARLs) were ultrasonically extracted from Allium roesum leaves then purified and analyzed by several techniques. Chemical composition and GC-MS analysis showed that the obtained polysaccharides were composed mainly of glucose (40.20 %), mannose (25.30 %), fructose (10.60 %) and galacturonic acid (15.11 %). Moreover, PARLs exhibited a potent antioxidant effect with higher capacities up to 69.61 % and 71.72 % for DPPH and ABTS free radicals, respectively. Furthermore, PARLs significantly modulated inflammatory response by reducing TNF-α, IL-6, and IL-8 pro-inflammatory mediators and promoting the anti-inflammatory IL-10 mediator in LPS stimulated THP-1 derived macrophages. The in-vivo tests proved that the extract was able to decrease carrageenan-induced rat paw swelling by around 68.15 % after 4 h of treatment. PARLs, significantly reduced the growth of U87 (glioblastoma) and IGROV-1 cancer cells with IC50 values of about 4.27 and 7.89 mg/mL respectively. This research clearly shows that Allium roseum polysaccharides can be used as natural antioxidants with anti-inflammatory and anticancer properties.

Extraction, purification, structural characterization and anti-hyperlipidemia activity of fucoidan from Laminaria digitata

Laminaria digitata is a high-quality seaweed resource that is widely cultured and has good application prospects. In this study, Laminaria digitata fucoidan (LF) was extracted from Laminaria digitata, and purified using DEAE-Sepharose Fast Flow gel column to obtain four different grades. Among those, LF4 (Mw:165 kDa), mainly composed of fucose(56.80 %), had the highest total sugar (66.91 %) and sulfate (17.07 %) content. FT-RT and NMR results showed that LF4 was mainly composed of galactosylated galactofucose, and has a sulfate group attached to fucose C4. With the animal experimentation, it was revealed that hyperlipidaemic mice had significantly higher levels of TC (5.52 mmol/L), TG (2.28 mmol/L) and LDL-C (5.12 mmol/L) and significantly lower levels of HDL-C (2 mmol/L). However, LF had the efficacy in modulating the lipid metabolism disturbances induced by hyperlipidemia, as well as the ability to regulate cholesterol transport in serum. Moreover, it regulated AMPK/ACC, PPAR-α/LAXRa, Nrf2/Nqo1, TLR4/NF-κB signaling pathway genes and proteins expression in the liver. In addition, it promoted the production of beneficial short-chain fatty acids (SCFAs) while improving the composition and structure of gut microbiota, including balancing the abundance of Bacteroidota, Firmicutes, Muribaculaceae, Alloprevotella, Escherichia-Shigella, Prevotella and NK4A136. The results clearly indicated that LF4 could significantly ameliorate hyperlipidemia, suggesting its prospective application as a functional food.

Astragali radix (Huangqi): a time-honored nourishing herbal medicine

Astragali radix (AR, namded Huangqi in Chinese) is the dried root of Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao or Astragalus membranaceus (Fisch.) Bge. As a widely used ethnomedicine, the biological activities of AR include immunomodulatory, anti-hyperglycemic, anti-oxidant, anti-aging, anti-inflammatory, anti-viral, anti-tumor, cardioprotective, and anti-diabetic effects, with minimum side effects. Currently, it is known that polysaccharides, saponins, and flavonoids are the indispensable components of AR. In this review, we will elaborate the research advancements of AR on ethnobotany, ethnopharmacological practices, phytochemicals, pharmacological activities, clinical uses, quality control, production developments, and toxicology. The information is expected to assist clinicians and scientists in developing useful therapeutic medicines with minimal systemic side effects.

The angelica Polysaccharide: a review of phytochemistry, pharmacology and beneficial effects on systemic diseases

Angelica sinensis is a perennial herb widely distributed around the world, and angelica polysaccharide (APS) is a polysaccharide extracted from Angelica sinensis. APS is one of the main active components of Angelica sinensis. A large number of studies have shown that APS has hematopoietic, promoting blood circulation, radiation resistance, lowering blood glucose, enhancing the body immunity and other pharmacological effects in a variety of diseases. However, different extraction methods and extraction sites greatly affect the efficacy of APS. In recent years, with the emerging of new technologies, there are more and more studies on the combined application and structural modification of APS. In order to promote the comprehensive development and in-depth application of APS, this narrative review systematically summarizes the effects of different drying methods and extraction sites on the biological activity of APS, and the application of APS in the treatment of diseases, hoping to provide a scientific basis for the experimental study and clinical application of APS.

Effects of high-pressure homogenization and ultrasound on the composition, structure, and physicochemical properties of proteins extracted from Nannochloropsis Oceania

This study examined the effects of high-pressure homogenization (HPH) and ultrasonication pre-treatment on the structural and physicochemical properties of proteins extracted from defatted Nannochloropsis Oceania biomass (DNOB). HPH treatment was found to enhance the solubility of protein extracted from DNOB compared to ultrasound, where samples pretreated with three passes (3P) of HPH exhibited lower solubility than two passes (2P). The morphology of extracted samples was visualized by scanning electron microscopy, which HPH pre-treatment, especially with more passes, were able to breakdown DNOB into fragments. Alternatively, more holes were displayed on the surface of the extracts pretreated with ultrasound especially when higher amplitude applied. The particle size of extracts from HPH3P (129.5 µm) significant dropped from HPH2P (314.25 µm), where samples pretreated with ultrasound at 20 % amplitude (US20) also decreased in particle size compared to 40 % amplitude (US40), from 115.25 µm to 78.22 µm. Protein flexibility of DNOB extracts were enhanced by both HPH2P and HPH3P but decreased for ultrasound samples. β-sheets were found to be the most abundant protein secondary structure for all samples, where samples treated with HPH3P contained the highest percentage of β-sheets (72 %) than control, HPH2P, ultrasonication at 20 and 40 % amplitude (52-62 %). The high percentage of β-sheets found in HPH3P sample also contributed to its outstanding emulsifying properties which stood out among all, especially at concentrations over 1 mg/ml. Results obtained from this study helped to direct the application of DNOB extracts as functional food ingredient for future food innovation.

Exploration of Polysaccharides from Phyllanthus emblica: Isolation, Identification, and Evaluation of Antioxidant and Anti-Glycolipid Metabolism Disorder Activities

Phyllanthus emblica is a natural medicinal herb with diverse bioactivities. Certain extracts from this herb have been confirmed to possess anti-glycolipid metabolic disorder activity. To further develop its utility value and explore its potential in combating glycolipid metabolic disorders, we designed a series of experiments to investigate the structure, antioxidant activity, and anti-glycolipid metabolic disorder activity of Phyllanthus emblica polysaccharides. In this study, we extracted and purified polysaccharides from Phyllanthus emblica and thoroughly analyzed their structure using various techniques, including NMR, methylation analysis, and surface-enhanced Raman spectroscopy. We investigated the hypolipidemic and anti-glycolipid metabolism disorder activity of Phyllanthus emblica polysaccharides for the first time utilizing oleic acid (OA) and advanced glycation end products (AGEs) as inducers. Additionally, the antioxidant activity of Phyllanthus emblica polysaccharides was assessed in vitro. These findings lay the groundwork for future investigations into the potential application of Phyllanthus emblica polysaccharides as an intervention for preventing and treating diabetes.

Traditional Chinese medicine polysaccharide in nano-drug delivery systems: Current progress and future perspectives

Traditional Chinese medicine polysaccharides (TCMPs) have gained increasing attention in the field of nanomedicine due to their diverse biological activities and favorable characteristics as drug carriers, including biocompatibility, biodegradability, safety, and ease of modification. TCMPs-based nano-drug delivery systems (NDDSs) offer several advantages, such as evasion of reticuloendothelial system (RES) phagocytosis, protection against biomolecule degradation, enhanced drug bioavailability, and potent therapeutic effects. Therefore, a comprehensive review of the latest developments in TCMPs-based NDDSs and their applications in disease therapy is of great significance. This review provides an overview of the structural characteristics and biological activities of TCMPs relevant to carrier design, the strategies employed for constructing TCMPs-based NDDSs, and the versatile role of TCMPs in these systems. Additionally, current challenges and future prospects of TCMPs in NDDSs are discussed, aiming to provide valuable insights for future research and clinical translation.

Effectiveness of Chinese Herbal Medicine as a Complementary Treatment for Neutropenia Prevention and Immunity Modulation During Chemotherapy in Patients With Breast Cancer: Protocol for a Real-World Pragmatic Clinical Trial

BACKGROUND

In recent years, advancements in cancer treatment have enabled cancer cell inhibition, leading to improved patient outcomes. However, the side effects of chemotherapy, especially leukopenia, impact patients' ability to tolerate their treatments and affect their quality of life. Traditional Chinese medicine is thought to provide complementary cancer treatment to improve the quality of life and prolong survival time among patients with cancer.

OBJECTIVE

This study aims to evaluate the effectiveness of Chinese herbal medicine (CHM) as a complementary treatment for neutropenia prevention and immunity modulation during chemotherapy in patients with breast cancer.

METHODS

We will conduct a real-world pragmatic clinical trial to evaluate the effectiveness of CHM as a supplementary therapy to prevent neutropenia in patients with breast cancer undergoing chemotherapy. Patients will be classified into CHM or non-CHM groups based on whether they received CHM during chemotherapy. Using generalized estimating equations or repeated measures ANOVA, we will assess differences in white blood cell counts, absolute neutrophil counts, immune cells, and programmed cell death protein 1 (PD-1) expression levels between the 2 groups.

RESULTS

This study was approved by the research ethics committee of Hualien Tzu Chi Hospital (IRB 110-168-A). The enrollment process began in September 2021 and will stop in December 2024. A total of 140 patients will be recruited. Data cleaning and analysis are expected to finish in the middle of 2025.

CONCLUSIONS

Traditional Chinese medicine is the most commonly used complementary medicine, and it has been reported to significantly alleviate chemotherapy-related side effects. This study's findings may contribute to developing effective interventions targeting chemotherapy-related neutropenia among patients with breast cancer in clinical practice.

TRIAL REGISTRATION

International Traditional Medicine Clinical Trial Registry ITMCTR2023000054; https://tinyurl.com/yc353hes.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/55662.

Specific molecular weight of Lycium barbarum polysaccharide for robust breast cancer regression by repolarizing tumor-associated macrophages

The pro-tumorigenic M2-type tumor-associated macrophages (TAMs) in the immunosuppressive tumor microenvironment (TME) promote the progression, angiogenesis, and metastasis of breast cancer. The repolarization of TAMs from an M2-type toward an M1-type holds great potential for the inhibition of breast cancer. Here, we report that Lycium barbarum polysaccharides (LBPs) can significantly reconstruct the TME by modulating the function of TAMs. Specifically, we separated four distinct molecular weight segments of LBPs and compared their repolarization effects on TAMs in TME. The results showed that LBP segments within 50-100 kDa molecular weight range exhibited the prime effect on the macrophage repolarization, augmented phagocytosis effect of the repolarized macrophages on breast cancer cells, and regression of breast tumor in a tumor-bearing mouse model. In addition, RNA-sequencing confirms that this segment of LBP displays an enhanced anti-breast cancer effect through innate immune responses. This study highlights the therapeutic potential of LBP segments within the 50-100 kDa molecular weight range for macrophage repolarization, paving ways to offer new strategies for the treatment of breast cancer.

Astragali Radix: comprehensive review of its botany, phytochemistry, pharmacology and clinical application

Astragali Radix (A. Radix) is the dried root of Astragalus membranaceus var. mongholicus (Bge) Hsiao or Astragalus membranaceus (Fisch.) Bge., belonging to the family Leguminosae, which is mainly distributed in China. A. Radix has been consumed as a tonic in China for more than 2000 years because of its medicinal effects of invigorating the spleen and replenishing qi. Currently, more than 400 natural compounds have been isolated and identified from A. Radix, mainly including saponins, flavonoids, phenylpropanoids, alkaloids, and others. Modern pharmacological studies have shown that A. Radix has anti-tumor, anti-inflammatory, immunomodulatory, anti-atherosclerotic, cardioprotective, anti-hypertensive, and anti-aging effects. It has been clinically used in the treatment of tumors, cardiovascular diseases, and cerebrovascular complications associated with diabetes with few side effects and high safety. This paper reviewed the progress of research on its chemical constituents, pharmacological effects, clinical applications, developing applications, and toxicology, which provides a basis for the better development and utilization of A. Radix.

Structural characterization and prebiotic activity of Bletilla striata polysaccharide prepared by one-step fermentation with Bacillus Licheniformis BJ2022

Bletilla striata polysaccharide (BP) is one of the main active ingredients in Orchidaceae plant Bletilla striata. BP has a high molecular weight, high viscosity, and complex diffusion, which is not conducive to the absorption and utilization of the human body. For the first time, we produced fermented Bletilla striata polysaccharide (FBP) with a low polymerization degree using Bacillus licheniformis BJ2022 one-step fermentation. FBP was a neutral polysaccharide with the molecular weight of 6790 Da. It was composed of glucose and mannose at a molar ratio of 1:2.7. The glycosidic bonds of FBP were composed of β-1,4-linked mannose, β-1,4-linked glucose and β-1,6-linked mannose according to methylation and NMR analysis. Compared with BP, FBP has a lower viscosity and higher solubility. The scanning electron microscopy results showed that the surface of FBP was porous and honeycomb-like. The rheology properties of FBP solution were close to non-Newtonian fluid. Using in vitro fermentation, we proved that FBP could regulate human gut microbiota and significantly increase the content of Bifidobacterium and Bacteroides. Our results suggested that Bacillus licheniformis fermentation significantly improved the physical and prebiotic properties of FBP. This study provides a new strategy for developing and utilizing Bletilla striata resources in China.

Characterization of Proteins Extracted from Ulva sp., Padina sp., and Laurencia sp. Macroalgae Using Green Technology: Effect of In Vitro Digestion on Antioxidant and ACE-I Inhibitory Activity

Macroalgal proteins were extracted from Ulva rigida (URPE) (green), Padina pavonica (PPPE) (brown), and Laurencia obtusa (LOPE) (red) using ultrasound-assisted enzymatic extraction, which is one of the green extraction technologies. Techno-functional, characteristic, and digestibility properties, and biological activities including antioxidant (AOA) and angiotensin-I converting enzyme (ACE-I) inhibitory activities were also investigated. According to the results, the extraction yield (EY) (94.74%) was detected in the extraction of L. obtusa, followed by U. rigida and P. pavonica. PPPE showed the highest ACE-I inhibitory activity before in vitro digestion. In contrast to PPPE, LOPE (20.90 ± 0.00%) and URPE (20.20 ± 0.00%) showed higher ACE-I inhibitory activity after in vitro digestion. The highest total phenolic content (TPC) (77.86 ± 1.00 mg GAE/g) was determined in LOPE. On the other hand, the highest AOACUPRAC (74.69 ± 1.78 mg TE/g) and AOAABTS (251.29 ± 5.0 mg TE/g) were detected in PPPE. After in vitro digestion, LOPE had the highest TPC (22.11 ± 2.18 mg GAE/g), AOACUPRAC (8.41 ± 0.06 mg TE/g), and AOAABTS (88.32 ± 0.65 mg TE/g) (p < 0.05). In vitro protein digestibility of three macroalgal protein extracts ranged from 84.35 ± 2.01% to 94.09 ± 0.00% (p < 0.05). Three macroalgae showed high oil holding capacity (OHC), especially PPPE (410.13 ± 16.37%) (p < 0.05), but they showed minimum foaming and emulsifying properties. The quality of the extracted macroalgal proteins was assessed using FTIR, SDS-PAGE, and DSC analyses. According to our findings, the method applied for macroalgal protein extraction could have a potential the promise of ultrasonication application as an environmentally friendly technology for food industry. Moreover, URPE, PPPE, and LOPE from sustainable sources may be attractive in terms of nourishment for people because of their digestibility, antioxidant properties, and ACE-I inhibitory activities.

Structural characterization, anti-tumor and immunomodulatory activity of intracellular polysaccharide from Armillaria luteo-virens

Armillaria luteo-virens (A. luteo-virens) is a kind of edible fungus mainly exists in Qinghai-Tibet of China, but at present only very few studies focus on the bioactivities of its polysaccharides. This study aimed to purify and characterize the structure features of a novel intracellular polysaccharide (ALP-A) derived from A. luteo-virens and explore its potential anti-tumor and immunomodulatory activities. Through systematic separation and purification, we obtained a homogeneous ALP-A with an average molecular weight of 23693Da. Structural analysis indicated that ALP-A was mainly composed of glucose and mannose with a molar ratio of 6.02:1. The repeating unit of ALP-A was →4) -α-D-Glcp-(1→ backbone with α-Glcp-(1→ and α-Manp-(6→ side chains which branched at O-2 position. The anti-tumor assays in vivo suggested that ALP-A could effectively restrain S180 solid tumor growth, protect immune organs and promote the secretion of cytokines (IL2, IL6 and TNF-α) in serum. Besides, in vitro immunomodulatory assays indicated that ALP-A could improve proliferation, phagocytic capacity and raise the level of NO and cytokines in Raw264.7 cells. These results demonstrate that ALP-A which possess potential antitumor and immunomodulatory abilities can be developed as a new functional food.

Mitigation of Hepatic Impairment with Polysaccharides from Red Alga Albidum corallinum Supplementation through Promoting the Lipid Profile and Liver Homeostasis in Tebuconazole-Exposed Rats

Sulfated polysaccharides from seaweed are highly active natural substances with valuable applications. In the present paper, attempts have been made to discuss the physicochemical and structural features of polysaccharides isolated from red marine alga Alsidium corallinum (ACPs) and their protective effect in hepatic impairments induced by tebuconazole (TEB) in male adult rats. Structural features were determined using high-performance liquid chromatography, Fourier-transformed infrared, and solid-state 1H and 13C-Nuclear magnetic resonance analysis. ACPs are found to be hetero-sulfated-anionic polysaccharides that contain carbohydrates, sulfate groups, and uronic acids. In vitro biological activities suggested the effective antioxidant and antimicrobial capacities of ACPs. For antioxidant testing in vivo, the biochemical analysis and plasma profiles displayed that oral administration of ACPs could mitigate blood lipid indicators, including total cholesterol, triglyceride, low and high-density lipoprotein cholesterol, and bilirubin. Liver function indexes involving alanine aminotransferase and aspartate aminotransferase showed that ACPs possessed prominent antioxidant activities. Additionally, the intervention of ACPs potentially inhibited lipid peroxidation, protein oxidation, key enzymes of lipid metabolism (<0.001), and improved antioxidant status (<0.05). Histomorphological observation confirmed that ACPs intervention could partially repair liver injuries caused by TEB. The computational results showed that A. corallinum monosaccharides bound 1JIJ, 1HD2, and 1WL4 receptors with acceptable affinities, which, together with deep embedding and molecular interactions, support the antioxidant, antimicrobial, and hypolipidemic outlined effects in the in vitro and in vivo findings. Given their prominent antioxidant effects, ACPs are promising candidates for liver diseases and must be considered in pharmaceutical applications.

Structure-activity relationship of low molecular weight Astragalus membranaceus polysaccharides produced by Bacteroides

Astragalus membranaceus polysaccharides (APS) possess significant biological activities, such as anti-tumor, antiviral, and immunomodulatory activities. However, there is still a lack of research on the structure-activity relationship of APS. In this paper, two carbohydrate-active enzymes from Bacteroides in living organisms were used to prepare degradation products. The degradation products were divided into APS-A1, APS-G1, APS-G2, and APS-G3 according to molecular weight. Structural analysis showed that all degradation products had an α-1,4-linked glucose backbone, but APS-A1 and APS-G3 also had branched chains of α-1,6-linked galactose or arabinogalacto-oligosaccharide. In vitro, immunomodulatory activity evaluation results indicated that APS-A1 and APS-G3 had better immunomodulatory activity, while the immunomodulatory activities of APS-G1 and APS-G2 were comparatively weaker. Molecular interaction detection showed that APS-A1 and APS-G3 could bind to toll-like receptors-4 (TLR-4) with a binding constant of 4.6 × 10^-5 and 9.4 × 10^-6, respectively, while APS-G1 and APS-G2 failed to bind to TLR-4. Therefore, the branched chains of galactose or arabinogalacto-oligosaccharide played a crucial role in the immunomodulatory activity of APS.

A novel heteropolysaccharide isolated from custard apple pulp and its immunomodulatory activity in mouse macrophages and dendritic cells

In this study, a novel heteropolysaccharide (ASPA80-1) with an average molecular weight of 5.48 × 104 Da was isolated and structurally elucidated from custard apple pulp (Annona squamosa) through DEAE-cellulose, Sephadex G-100 and Sephacryl S-300 HR chromatography and spectral analysis. ASPA80-1 is a water-soluble polysaccharide and it is a polymer consisting of predominant amounts of (1 → 3)-linked-L-arabinose (Ara) residues, small amounts of (1 → 6)-linked-D-galactose (Gal), (1 → 3,5)-linked-L-arabinose (Ara) residues and terminal linked-L-arabinose (Ara) residues, trace amount of (1 → 4)-linked-D-glucose (Glc) residues and (1 → 2)-linked-L-rhamnose (Rham) residues. ASPA80-1 showed significant effect on antigen-presenting cells (APCs) activation. On the one hand, ASPA80-1 activated RAW264.7 macrophage cells by inducing morphology change, enhancing phagocytic ability, increasing nitric oxide (NO) secretion and promoting expression of major histocompatibility complex class II (MHC II) and cluster of differentiation 86 (CD 86). On the other hand, ASPA80-1 promoted the maturation of dendritic cells (DCs) by inducing longer dendrites, decreasing phagocytic ability and increasing MHC II and CD86 expression. Furthermore, mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-κB) signaling pathways were activated after the intervention of ASPA80-1 on RAW264.7 cells or DCs. Thus, the novel heteropolysaccharide ASPA80-1 has the potential to be used as an immunoenhancing component in functional foods.

Purification, Structural Analysis and Cardio-Protective Activity of Polysaccharides from Radix Astragali

Two polysaccharides, named APS2-I and APS3-I, were purified from the water extract of Radix Astragali. The average molecular weight of APS2-I was 1.96 × 10⁶ Da and composed of Man, Rha, GlcA, GalA, Glc, Gal, Xyl, and Ara in a molar ratio of 2.3:4.8:1.7:14.0:5.8:11.7:2.8:12.6, while the average molecular weight of APS3-I was 3.91 × 10⁶ Da and composed of Rha, GalA, Glc, Gal, and Ara in a molar ratio of 0.8:2.3:0.8:2.3:4.1. Biological evaluation showed APS2-I and APS3-I had significant antioxidant activity and myocardial protection activity. Furthermore, total polysaccharide treatment could significantly enhance hemodynamic parameters and improve cardiac function in rat ischemia and reperfusion isolated heart models. These results provided important information for the clinical application of APS in the field of cardiovascular disease and implied that Astragalus polysaccharides (APS) could be considered as a reference for the quality control of Radix Astragali.

Controlled Drug Release from Nanoengineered Polysaccharides

Polysaccharides are naturally occurring complex molecules with exceptional physicochemical properties and bioactivities. They originate from plant, animal, and microbial-based resources and processes and can be chemically modified. The biocompatibility and biodegradability of polysaccharides enable their increased use in nanoscale synthesis and engineering for drug encapsulation and release. This review focuses on sustained drug release studies from nanoscale polysaccharides in the fields of nanotechnology and biomedical sciences. Particular emphasis is placed on drug release kinetics and relevant mathematical models. An effective release model can be used to envision the behavior of specific nanoscale polysaccharide matrices and reduce impending experimental trial and error, saving time and resources. A robust model can also assist in translating from in vitro to in vivo experiments. The main aim of this review is to demonstrate that any study that establishes sustained release from nanoscale polysaccharide matrices should be accompanied by a detailed analysis of drug release kinetics by modeling since sustained release from polysaccharides not only involves diffusion and degradation but also surface erosion, complicated swelling dynamics, crosslinking, and drug-polymer interactions. As such, in the first part, we discuss the classification and role of polysaccharides in various applications and later elaborate on the specific pharmaceutical processes of polysaccharides in ionic gelling, stabilization, cross-linking, grafting, and encapsulation of drugs. We also document several drug release models applied to nanoscale hydrogels, nanofibers, and nanoparticles of polysaccharides and conclude that, at times, more than one model can accurately describe the sustained release profiles, indicating the existence of release mechanisms running in parallel. Finally, we conclude with the future opportunities and advanced applications of nanoengineered polysaccharides and their theranostic aptitudes for future clinical applications.

The Large Molecular Weight Polysaccharide from Wild Cordyceps and Its Antitumor Activity on H22 Tumor-Bearing Mice

Cordyceps has anti-cancer effects; however, the bioactive substance and its effect are still unclear. Polysaccharides extracted from Cordyceps sinensis, the fugus of Cordyceps, have been reported to have anti-cancer properties. Thus, we speculated that polysaccharides might be the key anti-tumor active ingredients of Cordyceps because of their larger molecular weight than that of polysaccharides in Cordyceps sinensis. In this study, we aimed to investigate the effects of wild Cordyceps polysaccharides on H22 liver cancer and the underlying mechanism. The structural characteristics of the polysaccharides of WCP were analyzed by high-performance liquid chromatography, high-performance gel-permeation chromatography, Fourier transform infrared spectrophotometry, and scanning electron microscopy. Additionally, H22 tumor-bearing BALB/c mice were used to explore the anti-tumor effect of WCP (100 and 300 mg/kg/d). The mechanism by WCP inhibited H22 tumors was uncovered by the TUNEL assay, flow cytometry, hematoxylin-eosin staining, quantitative reverse transcription-polymerase chain reaction, and Western blotting. Here, our results showed that WCP presented high purity with an average molecular weight of 2.1 × 10⁶ Da and 2.19 × 10⁴ Da. WCP was determined to be composed of mannose, glucose, and galactose. Notably, WCP could inhibit the proliferation of H22 tumors not only by improving immune function, but also by promoting the apoptosis of tumor cells, likely through the IL-10/STAT3/Bcl2 and Cyto-c/Caspase8/3 signaling pathways, in H22 tumor-bearing mice. Particularly, WCP had essentially no side effects compared to 5-FU, a common drug used in the treatment of liver cancer. In conclusion, WCP could be a potential anti-tumor product with strong regulatory effects in H22 liver cancer.

Morphology, Solid Structure and Antioxidant Activity in Vitro of Angelica sinensis Polysaccharide-Ce(IV)

Angelica Sinensis polysaccharide cerium (ASP-Ce) was prepared by Angelica Sinensis polysaccharide (ASP) and cerium ammonium nitrate (NH₄ )₂ Ce(NO₃ )₆ . and its morphology, and solid structure was investigated. The antioxidant activity of the ASP-Ce complex in vitro was evaluated. The antioxidant activity of ASP-Ce complex in vitro was evaluated by the scavenging activity of 2,2-diphenyl-1-picrylhyrazyl radical (DPPH), hydroxyl radical (⋅OH) and superoxide anion radical ( O 2 - ${{{\rm O}}_{2}^{-}}$ ⋅). The results showed that the ASP-Ce had the more ordered structure for inserting the Ce⁴⁺ into the polymer chain of ASP and there was little change in the conformation of the polysaccharide from Ce⁴⁺ . Three free radical scavenging experiments proved that ASP-Ce had better antioxidant capacity than of ASP, especially on DPPH, and then on O 2 - ${{{\rm O}}_{2}^{-}}$ ⋅. The scavenging rate of ASP-Ce at 1.0 mg/mL on DPPH reached 71.6 %. Therefore, these results provide references for the further development and utilization of rare earth-polysaccharide.

Polysaccharides as antioxidants and prooxidants in managing the double-edged sword of reactive oxygen species

Polysaccharides, a class of naturally occurring carbohydrates, were widely presented in animals, plants, and microorganisms. Recently, health benefits of polysaccharides have attracted much attention due to their unique characteristics in reactive oxygen species (ROS) management. ROS, by-products of aerobic metabolism linked to food consumption, exhibited a dual role in protecting cells and fostering pathogenesis collectively termed double-edged sword. Some interesting studies reported that polysaccharides could behave as prooxidants under certain conditions, besides antioxidant capacities. Potentiation of the bright side of ROS could contribute to the host defense that was vitally important for the polysaccharides acting as biological response modifiers. Correspondingly, disease prevention of polysaccharides linked to the management of ROS production was systematically described and discussed in this review. Furthermore, major challenges and future prospects were presented, aiming to provide new insight into applying polysaccharides as functional food ingredients and medicine.

Structure and hepatoprotective activity of Usp10/NF-κB/Nrf2 pathway-related Morchella esculenta polysaccharide

The water-soluble Morchella esculenta polysaccharide 2 (MEP2) was purified and isolated from an aqueous extract of the Morchella esculenta fruiting bodies. MEP2, having a molecular weight of 959 kDa, has a →4)-α-D-Glcp-(1→ glucan backbone, and this branch was substituted at the H-6 position by an α-D-Glcp-(1 → 4)-α-D-Glcp-(1→ residue and an α-D-Glcp-(1→ residue. The hepatoprotective activity and potential mechanism of action of MEP2 were also investigated. MEP2 ameliorated severe liver damage and regulated the liver function indicators and the alcohol-related enzyme levels in chronic alcohol-induced mice. Combined with biochemical detection, the gut microbiota, metabolites, and proteomics results revealed that MEP2 regulates the levels of hepatic cytokines related to inflammatory response and oxidative stress, as well as those of intestinal Bacteroides, Oscillospira, Parabacteroides, Alistipes, and Prevotella, through the ubiquitin-specific peptidase 10 (Usp10)/nuclear factor κB (NF-κB)/nuclear factor erythroid-2 related factor 2 (Nrf2) signaling pathway in the liver of mice induced by long-term alcohol intake. These data provide experimental evidence for the application of MEP2 in chronic alcohol-induced liver injury.

Structural Characterization of Polysaccharides from Coriandrum sativum Seeds: Hepatoprotective Effect against Cadmium Toxicity In Vivo

Coriandrum sativum is one of the most widespread curative plants in the world, being vastly cultivated in arid and semi-arid regions as one of the oldest spice plants. The present study explored the extraction of polysaccharides from Coriandrum sativum seeds and the evaluation of their antioxidant potential and hepatoprotective effects in vivo. The polysaccharide from coriander seeds was extracted, and the structural characterization was performed by FT-IR, UV-vis, DSC, NMR (1D and 2D), GC-MS, and SEC analysis. The polysaccharide extracted from Coriandrum sativum (CPS) seeds was characterized to evaluate its antioxidant and hepatoprotective capacities in rats. Results showed that CPS was composed of arabinose, rhamnose, xylose, mannose, fructose, galactose, and glucose in molar percentages of 6.2%, 3.6%, 8.8%, 17.7%, 5.2%, 32.9%, and 25.6%, respectively. Further, CPS significantly hindered cadmium-induced oxidation damage and exercised a protective effect against Cd hepatocytotoxicity, with a considerable reduction in MDA production and interesting CAT and SOD enzyme levels. Results suggest that CPS might be employed as a natural antioxidant source.

Characterization of Polysaccharides Sequentially Extracted from Allium roseum Leaves and Their Hepatoprotective Effects against Cadmium Induced Toxicity in Mouse Liver

Allium roseum is one of the medicinal plants of the Liliaceae family, widely used in the food industry and traditional medicine. It is known for its various biological properties, such as its antioxidant, antiviral, antidiabetic, and anti-inflammatory activities. The present work aims to extract the polysaccharides from Allium roseum leaves and evaluate their antioxidant activities and hepatoprotective effects in vivo. Three polysaccharides from the leaves of Allium roseum were sequentially extracted in three media: water, chelating, and basic, respectively. They were characterized by size exclusion chromatography, gas chromatography mass spectrometry, FTIR-ATR, and NMR spectroscopy (1D and 2D). The different polysaccharides principally consist of glucose, galactose, mannose, rhamnose, xylose, and galacturonic acid. The antioxidant activity and hepatoprotective effect of the extracts against Cd-caused oxidative stress in liver mouse were tested. Cd treatment, during 24 h, enhanced significantly lipid peroxidation by a high production of malondyaldehyd (MDA) and superoxide dismutase (SOD) activity. In contrast, catalase activity (CAT) was decreased after the same period of exposure to the metal. The polysaccharides pre-treatment improved the antioxidant defense system to a great degree, mainly explained by the modulating levels of oxydative stress biomarkers (MDA, SOD, and CAT). This research clearly shows that Allium roseum polysaccharides, especially those extracted in aqueous medium, can be used as natural antioxidants with hepatoprotective properties.

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.

Two Novel Polysaccharides From Clitocybe squamulosa: Their Isolation, Structures, and Bioactivities

The crude polysaccharides from the fruiting bodies of Clitocybe squamulosa (CSFP) were isolated by hot-water extraction. Two novel polysaccharides, CSFP1-β and CSFP2-α, were further purified by DEAE-52 anion exchange and Sephacryl S-400 gel filtration chromatography, and the purities reached 98.44 and 97.83%, respectively. The structural characteristics and bioactivities of CSFP, CSFP1-β, and CSFP2-α were identified by the combination of chemical and instrumental analysis. Results showed that CSFP was formed by the aggregation of honeycomb spherical materials; CSFP1-β and CSFP2-α were interwoven by reticular and fibrous structures, respectively. Purified components of both CSFP1-β and CSFP2-α showed typical infrared absorption peaks of polysaccharides, and contents of nucleic acid and protein decreased significantly. Simultaneously, CSFP with a molecular weight (Mw) of 1.948 × 10⁴ Da were composed mainly of glucose, mannose, galactose, and rhamnose. CSFP1-β was composed mainly of glucose, galactose, and mannose, while CSFP2-α was composed of glucose, and both their Mw distributions were uneven. Compared with CSFP, the antioxidant activities of CSFP1-β and CSFP2-α were significantly improved (p < 0.05), and they both showed good abilities to bind free cholesterol and bile acid salts in vitro. The binding abilities of the two compounds were found to be 68.62 and 64.43%, and 46.66 and 45.05 mg/g, respectively. CSFP, CSFP1-β, and CSFP2-α had good bacteriostatic effects with a linear increasing relationship to increasing concentration. In addition, CSFP promoted the growth of RAW264.7 cells and has potential immunomodulatory, anti-inflammatory, and anti-tumor activities.

Antiviral Compounds Based on Natural ASTRAGALUS POLYSACCHARIDE (APS): Researches and Foresight in the Strategies for Combating SARS-CoV-2 (COVID-19)

Today, finding natural polymers with desirable properties for use in various industries is one of the critical axes of research in the world. Polysaccharides are a group of natural polymers that have various applications in the pharmaceutical industry. The attachment of monosaccharides forms polysaccharides through glycosidic bonds that are widely found in various sources, including plants. Genus Astragalus belongs to the Fabaceae family. Plants belonging to this genus have different polysaccharides. Astragalus polysaccharides (APS) have attracted a great deal of attention among natural polymers because they are non-toxic, biodegradable, and biocompatible. Currently, APS has great drug potential for curing or treating various diseases. Due to the different biological activities of polysaccharides, including Astragalus, this study has investigated the chemical structure of APS, research report on antiviral, anti-inflammatory, and stimulation of cytokine secretion by these polysaccharides. Also, in this study, the pharmaceutical approaches of APS compounds, as a natural, new and inexpensive source, have been discussed as suitable candidates for use in pharmaceutical formulations and preparation of new drugs to control COVID-19 infection.

Production of prebiotic gellan oligosaccharides based on the irradiation treatment and acid hydrolysis of gellan gum

Biologically active gellan oligosaccharides (GOSs), newly found plant elicitors and biostimulants, are produced from the hydrolysis of gellan gum. Traditional hydrolysis with concentrated acid suffers from the problems of high pollution and low functional oligosaccharide yield because the process is difficult to control. Irradiation (⁶⁰Co γ-ray) with a dosage ranging from 0 kGy to 175 kGy was used to degrade gellan gum efficiently and cleanly into low molecular weight (M_w) gellan with an average M_w ranging from 449,119 Da to 72,903 Da. The low M_w gellan irradiated at 70 kGy was further hydrolyzed with low concentration acid (0.5 mol/L HCl) to produce GOSs with DPs mainly 4 and 8, indicating that the Rha-β-(1 → 3)-Glc bonds in gellan gum were easily cut to produce residues with tetrasaccharide repeat subunits. Besides antioxidant activity, GOSs were also proved with prebiotic activity by in vitro fecal fermentation in a self-designed bionic intestinal reactor.

Molecular Insights into the Inhibitory Effect of GV971 Components Derived from Marine Acidic Oligosaccharides against the Conformational Transition of Aβ42 Monomers

GV971 derived from marine acidic oligosaccharides has been used to cure Alzheimer's disease (AD). However, the molecular mechanism of its inhibition of the conformational transition of amyloid β-proteins (Aβ) is still unclear. Herein, molecular dynamics simulations were used to explore the molecular mechanism of the main GV971 components including DiM, TetraM, HexaM, and OctaM to inhibit the conformational conversion of the Aβ42 monomer. It is found that the GV971 components inhibit the conformational transition from α-helix to β-sheet and the hydrophobic collapse of the Aβ42 monomer. In addition, the binding energy analysis implies that both electrostatic and van der Waals interactions are beneficial to the binding of GV971 components to the Aβ42 monomer. Among them, electrostatic interactions occupy the dominant position. Moreover, the GV971 components mainly interact directly with the charged residues D1, R5, K16, and K28 by forming salt bridges and hydrogen bonds, which specifically bind to the N-terminal region of Aβ42.

Sulfated Modification, Characterization and Potential Bioactivities of Polysaccharide From Ziziphus jujuba cv. Jinsixiaozao

In this study, jujube polysaccharide (JP) was extracted from Ziziphus jujuba cv. Jinsixiaozao and sulfated JP (SJP) was prepared. The optimum preparation conditions were as follows: reaction temperature 75°C, reaction time 1 h, ratio of chlorosulfonic acid-to-pyridine ( VCSA/ VPyr) 1. The degree of substitution of SJP was 0.664 ± 0.014. JP and SJP were typical heteropolysaccharides, which were composed of rhamnose, arabinose, xylose, mannose, glucose, and galactose, but the molar ratio of monosaccharides was different. Fourier transform infrared spectra showed that JP was sulfated successfully. Compared with JP, the molecular weight of SJP increased to 3.17 × 105 Da, its water solubility increased significantly, and its viscosity decreased significantly. When the microstructure of SJP was examined, it was found that the surface of the polysaccharides became loose and porous after sulfation. SJP had a higher hydroxyl radical scavenging activity than the unsulfated polysaccharide. Moreover, sulfation enhanced the antibacterial activity of the polysaccharides against Escherichia coli and Bacillus subtilis. Therefore, sulfation is an effective way to improve the biological activity of the polysaccharide, and SJP can be used as a potential antioxidant and antimicrobial agent in the field of food and medicine.

Study on the pharmacokinetics of mulberry fruit polysaccharides through fluorescence labeling

A sensitive and efficient fluorescence labeling method was developed and validated for the microanalysis and detection of polysaccharides. Fluorescein isothiocyanate (FITC) was successfully labeled on mulberry fruit polysaccharides (MFP) through a reductive amination reaction with the assistant of tyramine. The fluorescent labeled polysaccharides (FMFP) was identified by fluorescence, UV-visible, flourier transform infrared (FT-IR) and 1H NMR spectrum. Results demonstrated that the labeling efficiency of FMFP was 0.32%, and the FMFP was stable in simulated digestion fluid without cytotoxicity. The pharmacokinetics and biodistribution after administration were analyzed in rats, which indicated that the FMFP obtained could be absorbed in a short time (tmax 0.50 h) but eliminated slowly (t1/2 8.77 ± 1.38 h). At 24 h after administration, the polysaccharide could be tested mainly in intestine, stomach, liver and kidney. The FITC labeling method lays a foundation for investigating the absorption and metabolism of MFP, and provides references for the microanalysis research of bioactive polysaccharides.

Digestive properties and effects of Chimonanthus nitens Oliv polysaccharides on antioxidant effects in vitro and in immunocompromised mice

The study was aimed to investigate the simulated digestion behavior of the bioactive polysaccharides from Chimonanthus nitens Oliv (COP1), antioxidant activity in vitro, and prevention against cyclophosphamide (CP) induced oxidative damage in mice. The results showed that COP1 were 18.843 kDa, and consisted of arabinose (56.6 mol%), galactose (24.9 mol%), xylose (11.1 mol%), and glucose (7.4 mol%). Gastrointestinal digestion significantly improved the radical (DPPH, OH, and ABTS⁺) scavenging activities of COP1. Meanwhile, administration of COP1 (150, 300, and 600 mg/kg, continuous 16 days) prevented hepatotoxicity in CP-induced mice (reducing liver index and transaminase levels, alleviating liver damage). COP1 also attenuated oxidative stress as evident from as shown by reduced levels of MDA and enhanced activity of antioxidant enzymes (CAT, SOD, and GSH-Px). In addition, COP1 regulated the Nrf2/Keap1 signaling pathway in CP-treated mice, decreasing the upstream factor Keap1 and increasing the upstream factor Nrf2, which in turn enhanced the expression of downstream factors (NQO1, HO-1, GSH-Px, SOD1, and CAT). COP1 also protected the body from CP-induced oxidative damage by down-regulating Bax and caspase3 in the apoptosis pathway and up-regulating Bcl-2 mRNA levels. Overall, COP1 might be harnessed as an effective natural antioxidant for medical and food industries.

Rapid fingerprint analysis for herbal polysaccharides using direct analysis in real-time ionization mass spectrometry

RATIONALE

Herbal polysaccharides have various potential medicinal values. Development of reliable analytical method for the fingerprint analysis of polysaccharides is critical for their quality assessment, origin identification, and authenticity evaluation.

METHODS

Mechanochemical extraction (MCE) was used to extract polysaccharide components from different herbal species. Intact polysaccharides were then directly analyzed by direct analysis in real-time mass spectrometry (DART-MS). Standard addition method with isotope-labeled internal standard was used to quantify polysaccharide amounts directly from liquid extract. Multivariate data analysis was further conducted for species classification.

RESULTS

The intact and large polysaccharides were decomposed into small fragment ions less than m/z 350 instantaneously using DART ion source. Different polysaccharides showed distinguished fingerprint DART-MS spectra using both individual and mixed herbal species. The liquid supernatant from MCE was validated to be used as direct sample for DART-MS analysis. Quantitation was successfully achieved for polysaccharide contents in Dendrobium officinale from different locations.

CONCLUSIONS

A rapid fingerprint protocol in combination of MCE and DART-MS for herbal polysaccharides was developed. The whole process could be accomplished within a few minutes, from raw materials to final spectra, without requirements of pre-digestion and additional sample purification.

Astragalus Polysaccharides Enhance the Immune Response to OVA Antigen in BALB/c Mice

Vaccination has been identified as one of the most effective ways to prevent the transmission of infectious diseases in humans and animals. One of the most critical steps in vaccine development is the selection of a suitable adjuvant. Although various adjuvant candidates have been evaluated in the past few decades, only a limited amount of them are nontoxic and safe for human use. Astragalus polysaccharide (APS), due to its lack of toxicity, has been used as an immunomodulator to enhance immune responses. On the other hand, the immune effects of APS on ovalbumin are yet to be examined. Thus, in this study, we analyzed APS's effects on the immune response to ovalbumin in BALB/c mice. We have also used the classic adjuvant CpG oligodeoxynucleotide as the positive control.

Extraction, structure, pharmacological activities and drug carrier applications of Angelica sinensis polysaccharide

Angelica sinensis polysaccharide (ASP) is one of the main active components of Angelica sinensis (AS) that is widely used in traditional Chinese medicine. ASP is water-soluble polysaccharides, and it is mainly composed of glucose (Glc), galactose (Gal), arabinose (Ara), rhamnose (Rha), fucose (Fuc), xylose (Xyl) and galacturonic acid (GalUA). The extraction methods of ASP include hot water extraction and ultrasonic wave extraction, and different extraction methods can affect the yield of ASP. ASP has a variety of pharmacological activities, including hematopoietic activity, promoting immunity, antitumor, anti-inflammatory, antioxidant, anti-aging, anti-virus, liver protection, and so on. As a kind of natural polysaccharide, ASP has potential application as drug carriers. This review provides a comprehensive summary of the latest extraction and purification methods of ASP, the strategies used for monosaccharide compositional analysis plus polysaccharide structural characterization, pharmacological activities and drug carrier applications, and it can provide a basis for further study on ASP.

HILIC-MS-based metabolomics reveal that Astragalus polysaccharide alleviates doxorubicin-induced cardiomyopathy by regulating sphingolipid and glycerophospholipid homeostasis

Doxorubicin (DOX) is widely used against cancer but carries the risk of a progressive cardiomyopathy. Astragalus polysaccharides (ASP) is the main active ingredient of Astragalus membranaceus Bunge. It has been proved to be effective against DOX-induced cardiomyopathy. However, its therapeutic mechanism is not yet well explored. In this study, a metabolomics approach based on hydrophilic interaction liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HILIC-Q-TOFMS) was developed to characterize the metabolic fluctuations associated with DOX cardiomyopathy and elucidate the underlying mechanisms of the protective effects of ASP. By the combination of HILIC-Q-TOFMS and multivariate and univariate data analysis, we identified 22 polar serum metabolites associated with DOX cardiomyopathy, 12 of which were significantly reversed when the animals were co-treated with ASP through two main metabolic pathways, i.e., sphingolipid and glycerophospholipid metabolism. Furthermore, it was found that ASP could alleviate DOX-induced cardiomyopathy by decreasing the levels of acid sphingomyelinase, acid ceramidase and phospholipase A2 and increasing the levels of sphingomyelin synthase to regulate the sphingolipid and glycerophospholipid metabolic disorder. These results revealed that sphingolipid and glycerophospholipid metabolism may be significantly responsible for DOX cardiomyopathy, which is also a major mechanism for the action of ASP against DOX cardiomyopathy.

Astragaloside regulates lncRNA LOC100912373 and the miR‑17‑5p/PDK1 axis to inhibit the proliferation of fibroblast‑like synoviocytes in rats with rheumatoid arthritis

Previous studies have confirmed that astragaloside (AST) exerts a positive effect on alleviating synovial and joint injury in rheumatoid arthritis (RA). However, the precise mechanisms through which AST acts in the treatment of RA remain unclear. Long non-coding RNA (lncRNA) LOC100912373 was identified as a key gene related to RA and has been proven to interact with miR-17-5p, in order to regulate the pyruvate dehydrogenase kinase 1 and protein kinase B axis (PDK1/AKT axis). The present study aimed to determine whether AST may treat RA through the interaction between lncRNA LOC100912373 and the miR-17-5p/PDK1 axis. MTT assays and flow cytometry were used to detect the proliferation and cell cycle progression of AST-treated fibroblast-like synoviocytes (FLSs). The expression of lncRNA LOC100912373 and miR-17-5p, as well as relative the mRNA expression of the PDK1 and AKT genes following AST intervention was detected by reverse transcription-quantitative PCR (RT-qPCR), immunofluorescence and western blot analysis. The results revealed that AST inhibited FLS proliferation, reduced lncRNA LOC100912373 expression levels, increased miR-17-5p expression levels, and decreased the PDK1 and p-AKT expression levels. Additionally, consecutive rescue experiments revealed that AST counteracted the effects of lncRNA LOC100912373 overexpression on FLS proliferation and cell cycle progression. On the whole, the present study demonstrates that AST inhibits FLS proliferation by regulating the expression of lncRNA LOC100912373 and the miR-17-5p/PDK1 axis.

Purification, Structural Characterization and Immunomodulatory Effects of Polysaccharides from Amomumvillosum Lour. on RAW 264.7 Macrophages

Amomum Villosum Lour. (A. villosum) is a folk medicine that has been used for more than 1300 years. However, study of the polysaccharides of A. villosum is seriously neglected. The objectives of this study are to explore the structural characteristics of polysaccharides from A. villosum (AVPs) and their effects on immune cells. In this study, the acidic polysaccharides (AVPG-1 and AVPG-2) were isolated from AVPs and purified via anion exchange and gel filtration chromatography. The structural characteristics of the polysaccharides were characterized by methylation, HPSEC-MALLS-RID, HPLC, FT-IR, SEM, GC-MS and NMR techniques. AVPG-1 with a molecular weight of 514 kDa had the backbone of → 4)-α-d-Glcp-(1 → 3,4)-β-d-Glcp-(1 → 4)-α-d-Glcp-(1 →. AVPG-2 with a higher molecular weight (14800 kDa) comprised a backbone of → 4)-α-d-Glcp-(1 → 3,6)-β-d-Galp-(1 → 4)-α-d-Glcp-(1 →. RAW 264.7 cells were used to investigate the potential effect of AVPG-1 and AVPG-2 on macrophages, and lipopolysaccharide (LPS) was used as a positive control. The results from bioassays showed that AVPG-2 exhibited stronger immunomodulatory activity than AVPG-1. AVPG-2 significantly induced nitric oxide (NO) production as well as the release of interleukin (IL)-6 and tumor necrosis factor alpha (TNF-α), and upregulated phagocytic capacities of RAW 264.7 cells. Real-time PCR analysis revealed that AVPG-2 was able to turn the polarization of macrophages to the M1 direction. These results suggested that AVPs could be explored as potential immunomodulatory agents of the functional foods or complementary medicine.

Structural characteristics and immunostimulatory activities of a new polysaccharide from Dendrobium fimbriatum Hook

A new polysaccharide (cDFP-W1) with high immunostimulatory activities was isolated from the stems of Dendrobium fimbriatum Hook. The analysis of the physicochemical properties showed that cDFP-W1 consisted of mannose and glucose in a molar ratio of 1 : 3.84, and its relative molecular weight was 4.0 × 10⁴ Da. Structural analysis implied that the linear backbone of cDFP-W1 was composed of α-1,4-d-Glcp, β-1,4-d-Manp, 3-O-acetyl-α-1,4-d-Glcp and α-1,4,6-d-Glcp, and its branches were the terminal β-d-Manp that was attached to the C-6 position of α-1,4,6-d-Glcp. An in vivo immunostimulatory assay exhibited that cDFP-W1 at 200 mg kg^-1 could significantly increase the proportions of CD4⁺ T-cell subpopulations, B cells, natural killer cells and dendritic cells, decrease the proportion of CD8⁺ T-cell subpopulations, and upregulate the percentage of activated macrophages (p < 0.01) in the spleen of mice. An in vitro immunostimulatory assay revealed that cDFP-W1 could effectively promote the proliferation of spleen lymphocytes, enhance the proliferation and phagocytosis of macrophage RAW264.7 cells, and stimulate the mRNA expression and extracellular release of NO, TNF-α and IL-1β of RAW264.7 cells. The western blot experiment suggested that the immunostimulatory activities of cDFP-W1 were closely related to the activation of MAPKs, NF-κB and PI3K/Akt signaling pathways.