Monosaccharide composition and in vivo immuno-stimulatory potential of soluble yam (Dioscorea opposita Thunb.) polysaccharides in response to a covalent Se incorporation

Polysaccharides from traditional Chinese medicine and their nano-formulated delivery systems for cancer immunotherapy

Cancer immunotherapy has evolved into a new generation strategy in the field of anti-tumor treatment. Polysaccharides derived from Traditional Chinese Medicine (TCM) are gaining recognition as powerful immunomodulators in cancer therapy, noted for their multi-target and multi-pathway actions. Owing to their beneficial properties such as water solubility, biocompatibility, and chemical structure modifiability, TCM polysaccharides can also serve as carriers for hydrophobic drugs in the development of innovative drug delivery systems, enhancing synergistic antitumor effects. In this article, we summarize the diverse mechanisms of immunoregulation by TCM polysaccharides in tumor therapy. The applications of these polysaccharides as both active ingredients and drug carriers within nanodelivery systems for cancer immunotherapy are also introduced. Additionally, extensive research on TCM polysaccharides in clinical settings has been collected. Furthermore, discussions are presented on the development prospects and challenges faced by these polysaccharides in the field of tumor immunotherapy. Our goal is to improve researchers' comprehension of TCM polysaccharides in cancer immunotherapy, providing promising strategies to optimize cancer treatment and benefit diverse patient populations.

Microfluidic development of liposome nanoparticles encapsulated with yam polysaccharide

A novel liposome nanoparticle loaded with yam polysaccharide was developed in this study via a tailor-made microfluidic device and further optimized through the Box-Behnken Design method of surface analysis to exploit combinational immunomodulatory effects of liposomes and yam polysaccharide. A chip of 100 μm in height and 200 μm in width with a mixing channel with embedded baffles to enhance fluid mixing was first designed and fabricated. Liposome nanoparticles were obtained by manipulating the operating parameters of the microfluidic chip. The formulation of yam polysaccharide loaded liposomes (YPL1) was optimized using response-surface analysis, and their physicochemical properties were characterized. In vitro cellular assays were performed to assess the effect of YPL on the activity of mouse dendritic cells (DC) and the secretion of immune-related cytokines to investigate the immune-enhancing effect of YPL in vitro. The resulting YPL had a mean size of 154.2±3.8 nm with a narrow size distribution (PDI=0.083) and had a high entrapment efficiency (EE) of 79.02%. The YPL exhibited good stability at 4°C over 14 days of storage, and an in vitro sustained release duration of approximately 30 h. The YPL demonstrated excellent biocompatibility and stimulated the expression of immune-related cytokines, especially TNF-α. Therefore, the YPL with well controlled particle size and high loading capacity, capable of exhibiting potent immunostimulatory activity was successfully developed in this study via a microfluidic device and optimized using response-surface analysis. The current YPL engineering methodology could further serve as an experimental platform for liposome nanoparticle development.

Chinese yam polysaccharide induces the differentiation and natural antibody secretion of IgM+ B cells to prevent Aeromonas hydrophila infection in grass carp

Chinese yam polysaccharide (CYP) is an effective immunostimulant, however, its efficacy in grass carp, an important commercial fish species in Asia, remains untested. Here, our study evaluated the immunostimulatory effects of CYP on IgM+ B cells in vitro and on humoral immunity and immune defense against Aeromonas hydrophila infection in vivo. In vitro stimulation experiments showed that CYP could induce the secretion of IgM antibodies, because it could stimulate the proliferation and differentiation of head kidney IgM+ B cells. Moreover, CYP could also enhance the phagocytic activity of IgM+ B cells. When grass carp were intragastrically administrated (i.g.) with CYP, the serum IgM level increased, as did the capacity of serum IgM to bind to peptidoglycan (PGN) and lipopolysaccharide (LPS), indicating that CYP induced natural IgM production in grass carp. Correspondingly, the serum bactericidal ability to A. hydrophila enhanced. Immune protection experiments showed that CYP could protect grass carp from A. hydrophila infection in vivo, because the mortality rate and gut Aeromonas load of grass carp significantly decreased after CYP administration. Taken together, our study reveals immunostimulatory effects of CYP in grass carp, laying important foundation for the usage of CYP to control diseases in grass carp aquaculture.

Effects of selenylation on Chinese yam polysaccharides: Structure, antioxidant, and digestive properties

Natural polysaccharides have unsatisfactory properties in production and processing due to structural limitations. Recent studies have shown that chemical modifications can improve the physicochemical and functional properties of plant polysaccharides. Herein, the effect of selenylation on the structure, functional properties, and in vitro digestion characteristics of yam polysaccharide (YP) was investigated. Selenylated products with different selenium contents (YP-LSe and YP-HSe) were prepared by controlling the addition of sodium selenite, and all samples were identified as acidic polysaccharides. Selenylation induced alterations in the chemical composition of YP. FT-IR spectral analysis revealed that YP-LSe and YP-HSe exhibited characteristic vibrational absorption peaks associated with selenium-containing groups. Microstructure analysis showed that YP-LSe and YP-HSe presented stacked leaf-like structures with sphere attachments. Moreover, selenylation significantly enhanced the emulsion capacity, foaming capacity, and antioxidant capacity of YP. In the simulated digestion process, YP-LSe and YP-HSe exhibited greater resilience against the gastrointestinal environment than YP. This study provides a theoretical basis for the development and utilization of selenylation of YP in the field of functional foods.

The structure change of polygonatum polysaccharide and the protect effect of Polygonatum crtonema Hua extracts and polysaccharide on cisplatin-induced AKI mice during nine-steam-nine-bask processing

Polygonatum cyrtonema Hua (PC) with different processing degrees during the nine-steam-nine-bask processing was selected as the research object to investigate the changes of polysaccharide structure and their protective effect on cisplatin-induced acute kidney injury (AKI) in mice. The polysaccharides (PCP0, PCP4 and PCP9) were extracted, whose polysaccharide contents were 62.45 %, 60.34 % and 58.23 %, respectively. After processing, the apparent structure of PCPs became looser, and the apparent viscosity and the particle size were decreased. The PCPs were acidic polysaccharides containing pyran rings, and furan rings were present in PCP4 and PCP9. Besides, processing destroyed the original β-glucoside bond in PCP0. PCPs were all composed of Rha, Man, Glu, Gal, Xyl and Ara with different ratio. In addition, AKI mice model was successfully constructed by single intraperitoneal injection of 15 mg/kg cisplatin. PC extracts (3.0750 g/kg) and PCP (0.1599 g/kg) significantly decreased the kidney function, liver function, and percentage of renal cell apoptosis, and improved the kidney structure of AKI mice (p < 0.05). PC and PCP have protective effect on cisplatin-induced AKI mice, and the protective effect was improved with the increase of processing degree. Under the same processing degree, the protective effect of PC mixed extract was better than that of PCP.

The genus Dioscorea L. (Dioscoreaceae), a review of traditional uses, phytochemistry, pharmacology, and toxicity

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Dioscorea, a member of the Dioscoreaceae family, comprises approximately 600 species and is widely distributed across temperate and tropical regions such as Asia, South Africa, and North America. The traditional medicinal uses of Dioscorea have been documented in Asian and African pharmacological systems. In Asia, this genus is traditionally used to treat respiratory illnesses, rheumatism, diabetes, diarrhea, dysentery, and other conditions. In Africa, this genus has been used to treat human immunodeficiency virus and ring worms. However, the traditional medicinal practices in North America rarely mention the use of this genus.

AIM OF THE STUDY

The aim of this review is to comprehensively review the genus Dioscorea, focusing on its traditional uses, phytochemical constituents, pharmacological activities, and potential toxicities. The research also aims to highlight the valuable bioactive compounds within Dioscorea and emphasize the need for further investigations into acute and chronic toxicity, activity mechanisms, molecular markers, and other relevant factors to contribute to the discovery of novel pharmaceuticals.

MATERIALS AND METHODS

A search for available information on Dioscorea was conducted using scientific databases, including PubMed, ISI-WOS, Scopus, and Google Scholar, as well as recent academic publications from reputable publishers and other literature sources. The search was not limited by language and spanned the literature published between 1950 and 2022.

RESULTS

This article provides a comprehensive review of the Dioscorea genus, focusing on its traditional uses, phytochemical constituents, pharmacological activities, and potential toxicities. Extensive research has been conducted on this genus, resulting in the isolation and examination of over 1000 compounds, including steroids, terpenoids, and flavonoids, to determine their biological activities. These activities include anti-tumor, anti-inflammatory, immunomodulatory, neuroprotective, hypoglycemic, and hypolipidemic effects. However, some studies have indicated the potential toxicity of high doses of Dioscorea, highlighting the need for further investigations to assess the safety of this genus. Additionally, this review explores potential avenues for future research and discusses the challenges associated with a comprehensive understanding of the Dioscorea genus.

CONCLUSIONS

Based on the existing literature, it can be concluded that Dioscorea is a valuable source of bioactive compounds that have the potential to treat various disorders. Future research should prioritize the investigation of acute and chronic toxicity, activity mechanisms, molecular markers, and other relevant factors. This review provides a comprehensive analysis of the Dioscorea genus, emphasizing its potential to enable a deeper exploration of the biological activity mechanisms of these plants and contribute to the discovery of novel pharmaceuticals.

Prospects of yam (Dioscorea) polysaccharides: Structural features, bioactivities and applications

Yam (Dioscorea) is a tuber crop cultivated for food security, revenue, and medicinal purposes. It has been used to treat diabetes, asthma, diarrhea, and other diseases. The main active ingredients in yam, polysaccharides, are regarded to be the important reason for its widespread applications. Now, a comprehensive review of research developments of yam polysaccharides (YPs) was presented to explore their prospects. We outlined the structural characteristics, biological activities, structure-activity relationships, and potential applications. Around 13 neutral components and 17 acidic components were separated. They exhibited various bioactivities, including immunomodulatory, hypoglycemic, hypolipidemic, antioxidant, gastrointestinal protective, anti-fatigue, and senile disease treatment activities, as well as prebiotic effect. Structure-activity relationships illustrated that unique structural properties, chemical modifications, and carried biopolymers could influence the bioactivities of YPs. The potential applications in medicine, food, and other fields have also been summarized.

Research progress on the structure, derivatives, pharmacological activity, and drug carrier capacity of Chinese yam polysaccharides: A review

Chinese yam is a traditional Chinese medicine that has a long history of medicinal and edible usage in China and is widely utilised in food, medicine, animal husbandry, and other industries. Chinese yam polysaccharides (CYPs) are among the main active components of Chinese yam. In recent decades, CYPs have received considerable attention because of their remarkable biological activities, such as immunomodulatory, antitumour, hypoglycaemic, hypolipidaemic, antioxidative, anti-inflammatory, and bacteriostatic effects. The structure and chemical alterations of polysaccharides are the main factors affecting their biological activities. CYPs are potential drug carriers owing to their excellent biodegradability and biocompatibility. There is a considerable amount of research on CYPs; however, a systematic summary is lacking. This review summarises the structural characteristics, derivative synthesis, biological activities, and their usage as drug carriers, providing a basis for future research, development, and application of CYPs.