Sulfated Chinese yam polysaccharide enhances the immunomodulatory activity of RAW 264.7 cells via the TLR4-MAPK/NF-κB signaling pathway

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.

Protection effect of Dioscoreae Rhizoma against ethanol-induced gastric injury in vitro and in vivo: A phytochemical and pharmacological study

ETHNOPHARMACOLOGICAL RELEVANCE

Dioscoreae Rhizoma, a kind of Chinese yam, is a medicinal and edible plant used in China for strengthening the spleen and stomach. However, there is a lack of modern pharmacology studies regarding its anti-gastric injury activity.

AIM OF THE STUDY

This study aimed to investigate the phytochemical composition of Chinese yam aqueous extract (CYW) and evaluate its gastroprotective effects against ethanol-induced gastric injury in vitro and in vivo.

MATERIALS AND METHODS

The active components of CYW were identified using HPLC-QTOF-MS/MS in combination with the GNPS molecular networking and network pharmacology. In vitro studies were performed in the RAW264.7/GES-1 cell coculture system. In vivo study, mice were treated with CYW (0.31, 0.63, and 3.14 g/kg BW, orally) for 14 days, followed by a single oral dose of ethanol (10 mL/kg BW) to induce gastric injury. The biochemical, inflammation and oxidative stress markers were analyzed using commercial kits. Histopathology was used to assess the degree of gastric injury. Gene and protein expressions were studied using RT-qPCR and western blotting, respectively.

RESULTS

CYW significantly restored the levels of SOD, GPx and CAT, and reduced the MDA content. Further analyses showed that CYW significantly alleviated the gastric oxidative stress by inhibiting the inflammation via decreasing p-NF-κB and p-IκB-α expression levels and inhibiting the generation of IL-6, TNF-α, and IL-1β. At the same time, the fraction remarkably upregulated Bcl-2, downregulated Bax and increased growth factor secretion, thereby prevented gastric mucous cell. Besides, The combination of HPLC-QTOF-MS/MS, GNPS molecular networking analysis, and network pharmacology demonstrated that linoleic acid, 3-acetyl-11-keto-beta-boswellic acid, adenosine, aminocaproic acid, tyramine, DL-tryptophan, cycloleucine, lactulose, melibiose, alpha-beta-trehalose, and sucrose would be the main active compounds of CYW against ethanol-induced gastric injury.

CONCLUSION

This study showed that CYW is potentially rich source of anti-oxidant and anti-inflammatory bioactive compounds. It showed efficacy against ethanol-induced gastric injury by inhibiting inflammation, oxidative stress, and apoptosis in the stomach. The results of the current work indicate that Dioscoreae Rhizoma could be utilized as a type of natural resource for production of new medicine and functional foods to prevent and/or ameliorate ethanol-induced gastric injury.

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.

Unveiling the immunomodulatory mechanism of polysaccharides from Polygonum cyrtonema based on RNA-seq

This work aimed to illuminate the mechanism of Polygonatum cyrtonema polysaccharide (PCP-80%) triggered immune activation. Results showed that PCP-80% enhanced the protein expression of COX-2 and iNOS, along with increasing the release of NO, ROS, cytokines (TNF-α, IL-6) in RAW264.7 cells. RNA-seq analysis revealed 2160 differentially expressed genes (DEGs) following PCP-80% treatment, comprising 1142 up-regulated and 1018 down-regulated genes. In addition, for investigating possible regulatory mechanisms, the NF-κB, MAPKs, and JAK-STAT signaling pathways were also chosen based on bioinformatics analysis. Furthermore, these findings were further corroborated through Western blot experiments, validating the activation of JAK-STAT (reduction of JAK1 in cells and elevation of p-STAT3 in the nucleus), MAPK (elevation of p-p38, p-ERK1/2, and p-JNK), and NF-κB (elevation of p-IκBα in cells, reduction of cytoplasmic p65, and increase of nuclear content of p-p65) in macrophage activation induced by PCP-80%. Besides, the production of NO and TNF-α was decreased by the inhibitor of the three pathways. In conclusion, these findings provide strong evidence that PCP-80% effectively modulates the immune response of macrophages, with significant involvement of the JAK-STAT, MAPKs, and NF-κB signaling pathways.

Molecular Insights into the Macrophage Immunomodulatory Effects of Scrophulariae Radix Polysaccharides

Scrophulariae Radix (SR) has been widely used in Chinese herbal compound prescriptions, health care products and functional foods. The present study aimed to investigate the immunomodulatory activity of polysaccharides from SR (SRPs) in macrophages and explore the potential mechanisms. The results showed that four SRPs fractions (SRPs40, SRPs60, SRPs80 and SRPs100) had similar absorption peaks and monosaccharide compositions, but the intensities of absorption peaks and monosaccharide contents were distinguished. All SRPs fractions significantly enhanced the pinocytic activity, promoted the production of NO and TNF-α, increased the mRNA expressions of inflammatory factors (IL-1β, IL-6, TNF-α and PTGS2) and TLR2, and elevated the phosphorylation levels of p38, ERK, JNK, p65 and IκB. Moreover, the production of NO and TNF-α stimulated by SRPs was dramatically suppressed by anti-TLR2 antibody. These results indicated that SRPs activated macrophages through MAPK and NF-κB signaling pathways via recognition of TLR2.

Dioscoreae Rhizoma starch improves chronic diarrhea by regulating the gut microbiotas and fecal metabolome in rats

Chinese yam (Dioscorea opposite Thunb.) has been used as food and medicine to treat diarrhea for thousands of years. This article aimed to elucidate the potential mechanism of Dioscoreae Rhizoma starch in alleviating chronic diarrhea induced by rhubarb based on gut microbiotas and fecal metabolome. The administration of the Dioscoreae Rhizoma aqueous extracts, crude polysaccharides, and starch could improve diarrhea and alleviate intestinal injury in chronic diarrhea rats. The Dioscoreae Rhizoma starch displayed the most apparent effect on regulating intestinal microbiotas by increasing the abundance and diversity of microbiotas. At the genus level, there were 17 changed intestinal microbiotas in model rats, and the treatment with Dioscoreae Rhizoma starch regulated 11 microbiotas. Metabolomics analysis revealed that Dioscoreae Rhizoma starch could regulate abnormal fecal metabolites to alleviate diarrhea, and these metabolites are involved in phenylalanine, tyrosine, and tryptophan biosynthesis; tyrosine metabolism; vitamin B6 metabolism; and purine metabolism. This study will contribute to the further research and development of Dioscoreae Rhizoma starch.

Propolis-loaded nanostructured lipid carriers halt breast cancer progression through miRNA-223 related pathways: an in-vitro/in-vivo experiment

The most frequent malignant tumor in women is breast cancer, and its incidence has been rising every year. Propolis has been used for its antibacterial, antifungal, and anti-inflammatory properties. The present study aimed to examine the effect of the Egyptian Propolis Extract (ProE) and its improved targeting using nanostructured lipid carriers (ProE-NLC) in Ehrlich Ascites Carcinoma (EAC) bearing mice, the common animal model for mammary tumors. EAC mice were treated either with 5-fluorouracil (5-FU), ProE, ProE-NLC, or a combination of ProE-NLC and 5-FU. Their effect on different inflammatory, angiogenic, proliferation and apoptotic markers, as well as miR-223, was examined. ProE and ProE-NLC have shown potential anti-breast cancer activity through multiple interrelated mechanisms including, the elevation of antioxidant levels, suppression of angiogenesis, inflammatory and mTOR pathways, and induction of the apoptotic pathway. All of which is a function of increased miRNA-223 expression. The efficiency of propolis was enhanced when loaded in nanostructured lipid carriers, increasing the effectiveness of the chemotherapeutic agent 5-FU. In conclusion, this study is the first to develop propolis-loaded NLC for breast cancer targeting and to recommend propolis as an antitumor agent against breast cancer or as an adjuvant treatment with chemotherapeutic agents to enhance their antitumor activity and decrease their side effects. Tumor targeting by ProE-NLC should be considered as a future therapeutic perspective in breast cancer.

Effects of Low Molecular Weight Peptides from Red Shrimp (Solenocera crassicornis) Head on Immune Response in Immunosuppressed Mice

This study aimed to investigate the immunoenhancement effects of low molecular weight peptides (SCHPs-F1) from red shrimp (Solenocera crassicornis) head against cyclophosphamide (CTX)-induced immunosuppressed mice. ICR mice were intraperitoneally injected with 80 mg/kg CTX for 5 consecutive days to establish the immunosuppressive model and then intragastrically administered with SCHPs-F1 (100 mg/kg, 200 mg/kg, and 400 mg/kg) to investigate its improving effect on immunosuppressed mice and explore its potential mechanism using Western blot. SCHPs-F1 could effectively improve the spleen and thymus index, promoting serum cytokines and immunoglobulins production and upregulating the proliferative activity of splenic lymphocytes and peritoneal macrophages of the CTX-treated mice. Moreover, SCHPs-F1 could significantly promote the expression levels of related proteins in the NF-κB and MAPK pathways in the spleen tissues. Overall, the results suggested that SCHPs-F1 could effectively ameliorate the immune deficiency caused by CTX and had the potential to explore as an immunomodulator in functional foods or dietary supplements.

Sulfated Chinese Yam Polysaccharides Alleviate LPS-Induced Acute Inflammation in Mice through Modulating Intestinal Microbiota

This study aimed to test the preventive anti-inflammatory properties of Chinese yam polysaccharides (CYP) and sulfated Chinese yam polysaccharides (SCYP) on LPS-induced systemic acute inflammation in mice and investigate their mechanisms of action. The results showed that SCYP can efficiently reduce plasma TNF-α and IL-6 levels, exhibiting an obvious anti-inflammation ability. Moreover, SCYP reduced hepatic TNF-α, IL-6, and IL-1β secretion more effectively than CYP, and significantly altered intestinal oxidative stress levels. In addition, a 16S rRNA gene sequencing analysis showed that CYP regulated the gut microbiota by decreasing Desulfovibrio and Sutterella and increasing Prevotella. SCYP changed the gut microbiota by decreasing Desulfovibrio and increasing Coprococcus, which reversed the microbiota dysbiosis caused by LPS. Linear discriminant analysis (LDA) effect size (LEfSe) revealed that treatment with CYP and SCYP can produce more biomarkers of the gut microbiome that can promote the proliferation of polysaccharide-degrading bacteria and facilitate the intestinal de-utilization of polysaccharides. These results suggest that SCYP can differentially regulate intestinal flora, and that they exhibit anti-inflammatory effects, thus providing a new reference to rationalize the exploitation of sulfated yam polysaccharides.

Structural characterization and immunomodulatory activity of an exopolysaccharide from marine-derived Aspergillus versicolor SCAU141

Until now, relatively little is known about marine-derived fungal polysaccharides and their activities. Exopolysaccharide AVP141-A was isolated from the broth of marine-derived fungus Aspergillus versicolor SCAU141 and purified by Diethylaminoethyl-Sepharose Fast Flow and Sephadex G-100. The structural characteristics of AVP141-A was studied by chemical analysis together with high-performance gel permeation chromatography, ion chromatography, Fourier-transform infrared spectroscopy, gas chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy. The results showed that AVP141-A with the molecular weight of 5.10 kDa was mainly composed of →4)-α-D-Glcp-(1→, branched by α-D-Glcp-(1→ and →6)-α-D-Glcp-(1→ at C-6 positions of the glucan backbone. In particular, sulfate ester (approximately 3.62 %) was found in AVP141-A, which was frequently considered to occur in marine-derived microbial polysaccharides rather than other microbial polysaccharides. Furthermore, AVP141-A significantly enhanced the activity of the inflammatory factors NO, COX-2 and TNF-α in RAW264.7 macrophages by activating the MAPK/p38 and NF-κB/p65 pathways. In addition, metabolomic analysis revealed that most of the pathways with significant changes in RAW264.7 macrophages treated with AVP141-A were amino acid-related pathways, and arginine was the characteristic metabolite. In conclusion, this study identified AVP141-A as a marine fungus-derived sulfated exopolysaccharide with potential for development as an immune activator.

Structural Characterization and Anti-Nonalcoholic Fatty Liver Effect of High-Sulfated Ulva pertusa Polysaccharide

The high-sulfated derivative of Ulva pertusa polysaccharide (HU), with unclear structure, has better anti-hyperlipidmia activity than U pertusa polysaccharide ulvan (U). In this study, we explore the main structure of HU and its therapeutic effect against nonalcoholic fatty liver disease (NAFLD). The main structure of HU was elucidated using FT-IR and NMR (13C, 1H, COSY, HSQC, HMBC). The anti-NAFLD activity of HU was explored using the high-fat diet mouse model to detect indicators of blood lipid and liver function and observe the pathologic changes in epididymal fat and the liver. Results showed that HU had these main structural fragments: →4)-β-D-Glcp(1→4)-α-L-Rhap2,3S(1→; →4)-α-L-Rhap3S(1→4)-β-D-Xylp2,3S(1→; →4)-α-L-Rhap3S(1→4)-β-D-Xylp(1→; →4)-α-L-IdopA3S(1→4)-α-L-Rhap3S(1→; →4)-β-D-GlcpA(1→3)-α-L-Rhap(1→; →4)-α-L-IdopA3S(1→4)-β-D-Glcp3Me(1→; →4)-β-D-Xylp2,3S(1→4)-α-L-IdopA3S(1→; and →4)-β-D-Xylp(1→4)-α-L-IdopA3S(1→. Treatment results indicated that HU markedly decreased levels of TC, LDL-C, TG, and AST. Furthermore, lipid droplets in the liver were reduced, and the abnormal enlargement of epididymal fat cells was suppressed. Thus, HU appears to have a protective effect on the development of NAFLD.

Chemical Modification, Characterization, and Activity Changes of Land Plant Polysaccharides: A Review

Plant polysaccharides are widely found in nature and have a variety of biological activities, including immunomodulatory, antioxidative, and antitumoral. Due to their low toxicity and easy absorption, they are widely used in the health food and pharmaceutical industries. However, low activity hinders the wide application. Chemical modification is an important method to improve plant polysaccharides' physical and chemical properties. Through chemical modification, the antioxidant and immunomodulatory abilities of polysaccharides were significantly improved. Some polysaccharides with poor water solubility also significantly improved their water solubility after modification. Chemical modification of plant polysaccharides has become an important research direction. Research on the modification of plant polysaccharides is currently increasing, but a review of the various modification studies is absent. This paper reviews the research progress of chemical modification (sulfation, phosphorylation, acetylation, selenization, and carboxymethylation modification) of land plant polysaccharides (excluding marine plant polysaccharides and fungi plant polysaccharides) during the period of January 2012-June 2022, including the preparation, characterization, and biological activity of modified polysaccharides. This study will provide a basis for the deep application of land plant polysaccharides in food, nutraceuticals, and pharmaceuticals.

Gas chromatography (GC) fingerprinting and immunomodulatory activity of polysaccharide from the rhizome of Menispermum dauricum DC

This research aimed to establish the gas chromatography (GC) fingerprints and examine the immunomodulatory activity of the rhizome of Menispermum dauricum polysaccharides. In this study, the preparation conditions were optimized by the response surface method (RSM). GC is an effective and sensitive technique employed to measure the composition of monosaccharides; the GC fingerprints of total polysaccharides from 10 batches of the rhizome of M. dauricum (tMDP) were established, and chemometrics methods were adopted to examine the differences and similarities of tMDP from distinct regions. The similarity evaluation illustrated that the polysaccharides derived from the rhizome of M. dauricum from different origins were highly similar. The results of principal components analysis (PCA) illustrated that all the tMDPs may be integrated into one group within the 95% confidence interval, but the rhizome of M. dauricum from different origins could also be distinguished in the plot of PCA scores. Then, the major bioactive fraction MDP was purified and obtained by column chromatography. Our previous study showed that MDP exhibited significant immunomodulatory activity, but the mechanism of the in vitro immunomodulatory activity of MDP is unclear. The macrophage activation induced by MDP was abolished when Toll-like receptor 4 (TLR4) signaling was knocked down by the TLR4 inhibitor. Furthermore, western blot analysis illustrated that MDP activated RAW264.7 cells through MAPKs and NFκB pathways induced by TLR4. This research offers a theoretical foundation for quality control and additional study as a potential immunomodulator of MDP.

Chinese yam polysaccharides PLGA-stabilized Pickering emulsion as an adjuvant system for PCV- 2 vaccine to enhance immune response

Chinese yam polysaccharides (CYP) exhibit superior adjuvant activity and modulate the immune response, but the low bioavailability limits their clinical application. Pickering emulsions have been proven as an efficient vaccine delivery system to enhance the immune response. Here, we used the Chinese yam polysaccharides PLGA-stabilized Pickering emulsion adjuvant system (CYP-PPAS) loaded with Porcine circovirus 2 as a vaccine and focused on investigating its adjuvant activity on humoral and cellular immunity in mice. The CYP-PPAS increased PCV-2 antigen loading efficiency and showed a high antigen uptake efficiency by macrophages in vitro. In vivo, CYP-PPAS significantly facilitated DCs maturation in draining lymph nodes than CYP or PPAS alone group. The CYP-PPAS also induced an increased proliferation index and a CD4⁺/CD8⁺ ratio. Meanwhile, in contrast to the CYP and PPAS groups, CYP-PPAS elicited a stronger anti-PCV-2 IgG and mixed Th1/Th2 immune response. Specifically, the CYP-PPAS group displayed the high expression of CD107a, FasL, and Granzyme B secretion to augment a strong cytotoxic lymphocyte response. Overall, the CYP-PPAS was a successful adjuvant system for promoting humoral and cellular immune responses, which opens up an avenue for the development of effective adjuvants against infectious diseases.