Immune-enhancing activity of Hydrangea macrophylla subsp. serrata leaves through TLR4/ROS-dependent activation of JNK and NF-κB in RAW264.7 cells and immunosuppressed mice

The Immune-Enhancing Effects of a Lactobacillus paracasei L-30 Extract Through the NF-κB and MAPK Pathways in RAW264.7

Immune enhancement is an important factor that not only helps prevent infections but also affects overall health. This study aims to evaluate the immunostimulatory effects of a novel Lactobacillus strain, Lactobacillus paracasei L-30, and to elucidate its underlying mechanisms. The extract obtained from Lactobacillus paracasei L-30 significantly increased phagocytosis and the production of NO and ROS in RAW264.7 macrophages. The protein and mRNA expression levels of COX-2 and iNOS which are immune regulators were upregulated by the L-30 extract. The levels of cytokines and chemokines, such as G-CSF, IL-6, MIP-1α, MIP-1γ, RANTES, sTNF RI, and sTNF RII, were increased by the treatment with the L-30 extract. In addition, the L-30 extract degraded IκB-α and induced the phosphorylation of NF-κB. Furthermore, the MAPK signaling pathways ERK, JNK, and p38 were activated by the L-30 extract. The production of iNOS, COX-2, and NO was inhibited by MAPK pathway inhibitors. Therefore, our data suggest that the Lactobacillus paracasei L-30 extract has the potential to be developed as a healthy functional food that can enhance immune responses by activating macrophages.

Virus-Induced Gene Silencing (VIGS) in Hydrangea macrophylla and Functional Analysis of HmF3'5'H

Hydrangea macrophylla, renowned for its large inflorescences and a diverse range of colors, highlights a significant limitation in current gene function research, which is the lack of effective molecular genetic tools. This study utilized a tobacco rattle virus (TRV)-based virus-induced gene silencing (VIGS) system to investigate gene function through posttranscriptional gene silencing in H. macrophylla for the first time. The ortholog of phytoene desaturase (PDS) in H. macrophylla, termed HmPDS, was identified. Infection of tissue-cultured seedlings with TRV-HmPDS led to photobleaching of the leaves. Additionally, infection with TRV containing the HmCHS1 fragment in the flowers resulted in decreased anthocyanin production in sepals and a lightening of sepal coloration in the infected flowers. The phenomena and RT-qPCR results proved that the PDS and CHS genes of hydrangea were successfully silenced via the vacuum infiltration method. Furthermore, the introduction of TRV-HmF3'5'H revealed a decrease in delphinidin-3-glucoside content in sepals and caused a color change in the sepals from blue to pink. This study demonstrated that the TRV-VIGS system was successfully established in H. macrophylla and effectively applied to the function analysis of HmF3'5'H.

Brassica rapa L. (Tibetan Turnip) polysaccharide improves the immune function and regulates intestinal microbiota in immunosuppressive mice

In this paper, active polysaccharides were extracted from Brassica rapa L. polysaccharide (BRP), and structural characterization was preliminarily investigated. Its immunomodulatory activity and molecular biological mechanisms in cyclophosphamide-induced immunosuppressed mice were also explored, as well as its effects on intestinal microbiota. Results indicate that BRP is an acidic heteropolysaccharide with the main components of Ara, GalA, and GlcA and has α- and β-glycosidic linkages with pyranose bonds. The results of the study showed that BRP could effectively improve the thymus and spleen indices and repair Cy-induced immune tissue damage in immunosuppressed mice. Meanwhile, BRP increased the immune cell activity and antioxidant levels in mice. In addition, BRP increased the secretion of cytokines (IL-1β, IL-6, IL-10, and TNF-α) and immunoglobulins (IgA, IgG) in mouse serum. It also regulates the relative expression of genes related to the TLR4/NF-κB signaling pathways as well as regulates the diversity and composition of mouse intestinal microbiota. In conclusion, BRP was able to regulated the immune function in immunosuppressed mice, providing a theoretical basis for the development of immunomodulators.

Screening immunomodulatory Q-markers in Astragali Radix based on UHPLC-QTOF-MS analysis and spectrum-effect relationship

Astragali Radix (AR) is one of the famous traditional Chinese medicines (TCMs) for boosting immunity, whereas the quality markers (Q-markers) of AR have not been clearly researched. The immunomodulatory activities of the bioactive extractions and components were evaluated by NO inhibition rate; phagocytic index; IL-10, TNF-α, IL-1β, and IL-6 cytokines in RAW264.7 cells; and the relative proliferation rate of spleen cells. The total saponins (TS) and the grade 2 (Xiaoxuan, XX) of AR showed the strongest immunomodulatory activities. At the concentration of 40 μg/mL, the TS increased spleen cells proliferation by 48.0% and upregulated the level of IL-1β and IL-6. Cytokines in the XX-treated group were at least 1.6 times higher than the control group. A total of 190 common peaks were detected in AR by ultrahigh-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UHPLC-QTOF-MS). The multivariate statistical analyses revealed that 41 compounds were positively correlated with immune responses, and bioactive compounds were verified by using RAW264.7 cell assay. Subsequently, the contents of six compounds in different commercial grades were determined, and the results showed the same trend in contents and activities. Finally, calycosin-7-O-β-D-glucoside, astragaloside IV, astragaloside II, astragaloside I, isomucronulatol-7-O-glucoside, and 9,10-dimethoxypterocarpan-3-O-glucoside were screened out as immunomodulatory Q-markers of AR.

Phyllodulcin from the hexane fraction of Hydrangea macrophylla inhibits glucose-induced lipid accumulation and reactive oxygen species generation in Caenorhabditis elegans

We confirmed that the hexane layer of Hydrangea macrophylla leaf extract (HLH) is rich in phyllodulcin (PD), an alternative sweetener, through high performance liquid chromatography (HPLC) analysis. To investigate in vivo activity of HLH and its PD, acute toxicity and growth rate of Caenorhabditis elegans were tested and there are no clinical abnormalities at 125-500 µg/mL of HLH. HLH decreased the total lipid and triglyceride contents dose-dependently in glucose-induced obese worms. Also, HLH increased survival rates under oxidative and thermal stress and decreased body reactive oxygen species (ROS) contents significantly. Such antioxidant properties of HLH were attributed to the enhanced activity of the antioxidant enzyme catalase. To determine whether the effect of HLH was due to PD, worms were treated with PD (concentration contained in HLH), and inhibitory effects on total lipids and ROS were observed. Our results suggest that HLH and its PD as a natural alternative sweetener can be used as materials to improve metabolic diseases.

In vitro immune-enhancing effects of Platycodon grandiflorum combined with Salvia plebeian via MAPK and NF-κB signaling in RAW264.7 cells

The immune-enhancing activity of the combination of Platycodon grandiflorum and Salvia plebeian extracts (PGSP) was evaluated through macrophage activation using RAW264.7 cells. PGSP (250-1000 μg/mL) showed a higher release of NO in a dose-dependent manner. The results showed that PGSP could significantly stimulate the production of PGE2, COX-2, TNF-α, IL-1β, and IL-6 in RAW264.7 cells and promote iNOS, COX-2, TNF-α, IL-1β, IL-4, and IL-6 mRNA expression. Western blot analysis demonstrated that the protein expression of iNOS and COX-2 and the phosphorylation of ERK, JNK, p38, and NF-κB p65 were greatly increased in PGSP-treated cells. PGSP also promoted the phagocytic activity of RAW264.7 cells. All these results indicated that PGSP might activate macrophages through MAPK and NF-κB signaling pathways. Taken together, PGSP may be considered to have immune-enhancing activity and might be used as a potential immune-enhancing agent.

Purification and characterization of a glycoprotein from Sipunculus nudus and its immune-enhancing activity to RAW 264.7 macrophages

Sipunculus nudus, an edible marine invertebrate, has long been used as traditional Chinese medicine in folk remedies. In order to assess the immunoregulatory activity of glycoproteins in Sipunculus nudus and conduct a structure-activity relationship, a glycoprotein (SGP1) with molecular mass of 9.26 kDa was purified from Sipunculus nudus, and its chemical structure as well as immune-enhancing activity was investigated in this study. Structure analysis revealed that SGP1, a protein-dominate glycoprotein with O-glycosidic bonds, contained 92.8 % protein and 3.1 % saccharide. GC-MS result indicated that the saccharide moieties of SGP1 basically consisted of lyxose (Lyx), xylose (Xyl) as well as glucose (Glu) at a molar proportion of 0.87:4.16:1.36. The fourier transform infrared specoscopy (FT-IR) result proved that SGP1 have a typical characteristic of glycoprotein. Besides, circular dichroism (CD) result showed that SGP1 contained 4.1 % α-helix, 42.5 % β-sheet, 21.4 % β-turn, and 32.0 % random coil, indicating it's mainly a β-sheet glycoprotein. The amino acid sequence of SGP1 shared a similarity to the Myohemerythrin (sp|Q5K473|HEMTM) with protein sequence coverage of 28.3 %. Moreover, the activity evaluation results showed that SGP1 exhibited significant immune-enhancing activity to the RAW 264.7 macrophages by promoting macrophages proliferation, enhancing phagocytic capacity, and simultaneously stimulating the secretions of nitric oxide (NO), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) via NF-κB pathways. In this study, SGP1 as a novel glycoprotein had an obvious immune-enhancing activity to macrophages, and thus could be applied in the functional foods as a potential immunopotentiator for the hypoimmune population.

Structural, physicochemical, and immune-enhancing properties of edible insect protein isolates from Protaetia brevitarsis larvae

Edible insects are promising future food resources globally. Herein, the structural, physicochemical, and bio-functional properties of edible insect protein isolates (EPIs) extracted from Protaetia brevitarsis larvae were investigated. The results showed that EPIs have a high total essential amino acid content; moreover, β-sheet is the major secondary protein structure. The EPI protein solution was highly soluble and electrically stable and did not aggregate easily. In addition, EPIs exhibited immune-enhancing properties; EPI treatment of macrophages induced the activation of macrophages and consequently promoted the production of pro-inflammatory mediators (NO, TNF-α, and IL-1β). Moreover, macrophage activation of EPIs was confirmed to occur through the MAPK and NF-κB pathways. In conclusion, our results suggest that the isolated P. brevitarsis protein can be fully utilized as a functional food material and alternative protein source in the future food industry.

The role of the ferroptosis pathway in the regulation of polysaccharides for human health: A review

Polysaccharides are natural polymers with ketone or aldehyde groups that are widely found in plants, animals, and microorganisms. They exhibit various biological activities and have potential development value in the food and pharmaceutical fields. Ferroptosis is a recently discovered modality that modulates cell death and has attracted considerable attention because it is considered to be involved in many pathophysiological processes. The inhibition of ferroptosis by reducing intracellular iron accumulation and lipid peroxidation may provide potential protective strategies against related pathologies. Ferroptosis is also involved in the physiological activities of polysaccharides, and its regulatory mechanism varies according to different physiological activities. However, a systematic summary on the involvement of ferroptosis in the physiological activities of polysaccharides is currently lacking. Therefore, this review systematically summarized the relationship between the physiological activities of polysaccharides and ferroptosis and focused on the regulatory mechanism of ferroptosis, with respect to the anti-cancer, anti-inflammatory, antioxidant, and immunomodulatory activities of all polysaccharides. The primary objective was to find new polysaccharide-related therapeutic breakthroughs for related diseases and to provide a reference for further research on polysaccharides-based therapeutics.

Immunostimulatory activity of Lactococcus lactis LM1185 isolated from Hydrangea macrophylla

The lactic acid bacteria, Lactococcus lactis subsp. lactis LM1185 was isolated from Hydrangea macrophylla. Strain LM1185 showed 50.5% of acid tolerance at pH 2.5 for 2 h and 30.4% of 0.3% (w/v) bile salt tolerance for 24 h. The antioxidant activity of this strain was measured at 99.4% of 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity. When RAW 264.7 macrophage cells were treated with strain LM1185, there was no observed cytotoxicity. This strain showed high nitric oxide production and mRNA expression levels of cytokines such as tumor necrosis factor-α and inducible nitric oxide synthase (iNOS). The nuclear factor-kB signaling pathway was activated by this strain resulting in the production of iNOS and cyclooxygenase-2 determined by western blotting. The present results indicated that L. lactis subsp. lactis LM1185 could be used as potential probiotics and may play a crucial role in the immunostimulatory effect on macrophages.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-022-01199-5.

Immunostimulatory Activity of Lactic Acid Bacteria Cell-Free Supernatants through the Activation of NF-κB and MAPK Signaling Pathways in RAW 264.7 Cells

Lactic acid bacteria (LAB) can improve host health and has strong potential for use as a health functional food. Specific strains of LAB have been reported to exert immunostimulatory effects. The primary goal of this study was to evaluate the immunostimulatory activities of novel LAB strains isolated from humans and foods and to investigate the probiotic properties of these strains. Cell-free supernatants (CFS) obtained from selected LAB strains significantly increased phagocytosis and level of nitric oxide (NO) and pro-inflammatory cytokines such as tumor necrosis factor (TNF)-α and interleukin (IL)-6 in RAW264.7 macrophage cells. The protein expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2, which are immunomodulators, was also upregulated by CFS treatment. CFS markedly induced the phosphorylation of nuclear factor-κB (NF-κB) and MAPKs (ERK, JNK, and p38). In addition, the safety of the LAB strains used in this study was demonstrated by hemolysis and antibiotic resistance tests. Their stability was confirmed under simulated gastrointestinal conditions. Taken together, these results indicate that the LAB strains selected in this study could be useful as probiotic candidates with immune-stimulating activity.

Immunomodulatory Effects of an Aqueous Extract of Black Radish on Mouse Macrophages via the TLR2/4-Mediated Signaling Pathway

Here, we determined the immunostimulatory effects of black radish (Raphanus sativus ver niger) hot water extract (BRHE) on a mouse macrophage cell line (RAW 264.7) and mouse peritoneal macrophages. We found that BRHE treatment increased cell proliferation, phagocytic activity, nitric oxide (NO) levels, cytokine production, and reactive oxygen species synthesis. Moreover, BRHE increased the expression of the following immunomodulators in RAW 264.7 cells and peritoneal macrophages: pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α), iNOS, and COX-2. BRHE treatment significantly up-regulated the phosphorylation of components of the mitogen-activated protein kinase (MAPK), nuclear factor-κB (NF-κB), Akt, and STAT3 signaling pathways. Further, the effects of BRHE on macrophages were significantly diminished after the cells were treated with the TLR2 antagonist C29 or the TLR4 antagonist TAK-242. Therefore, BRHE-induced immunostimulatory phenotypes in mouse macrophages were reversed by multiple inhibitors, such as TLR antagonist, MAPK inhibitor, and Akt inhibitor indicating that BRHE induced macrophage activation through the TLR2/4-MAPK-NFκB-Akt-STAT3 signaling pathway. These results indicate that BRHE may serve as a potential immunomodulatory factor or functional food and provide the scientific basis for the comprehensive utilization and evaluation of black radish in future applications.

The immune-enhancing effect and in vitro antioxidant ability of different fractions separated from Colla corii asini

In this study, Colla corii asini (CCA) was fractionated into three fractions with different molecular weights using ultracentrifugation equipment. Components with a molecular weight of >10 kDa in F1 accounted for 81.90%, whereas that in F2 and F3 was 15.63% and 0.94%, respectively. The immunomodulatory activity of CCA fractions was investigated using RAW264.7 cell model and their antioxidant abilities were evaluated by 2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) and ferric-reducing antioxidant power (FRAP) assay. The results indicated that RAW264.7 cells treated with F1 released the highest level of nitric oxide, reactive oxygen species, interleukin-6, and tumor necrosis factor-α. The ABTS and FRAP value of F1 were 65.81% and 29.33 μM TE/L, respectively, which were 22.53%, 128.44% and 43.72%, 132.16% higher than that of F2 and F3, respectively. These results suggested that components with a molecular weight of >10 kDa in CCA had stronger immunomodulatory and antioxidant ability, which would help develop the health food based on CCA. PRACTICAL APPLICATIONS: Colla corii asini (CCA) is a famous protein-based traditional Chinese medicine and nutritional supplement. During the processing of CCA, the molecular weight (MW) of CCA collagen components changed dynamically due to the protein aggregation, degradation, and the Maillard reaction. Some studies have shown that the MW distribution of CCA was not uniform. However, the MW range of CCA components which has strong antioxidant and immunomodulatory activity is still not clear, and few studies have reported the mechanism of CCA's immunomodulatory activity and active ingredients. Therefore, it is important to figure out the characteristics of CCA components with stronger immunomodulatory and antioxidant ability, such as the MW distribution and chemical composition of CCA fractions. And this study will be great for the processing of CCA products which has better biological functions.

Metal Ion Periplasmic-Binding Protein YfeA of Glaesserella parasuis Induces the Secretion of Pro-Inflammatory Cytokines of Macrophages via MAPK and NF-κB Signaling through TLR2 and TLR4

The YfeA gene, belonging to the well-conserved ABC (ATP-binding cassette) transport system Yfe, encodes the substrate-binding subunit of the iron, zinc, and manganese transport system in bacteria. As a potential vaccine candidate in Glaesserella parasuis, the functional mechanisms of YfeA in the infection process remain obscure. In this study, vaccination with YfeA effectively protected the C56BL6 mouse against the G. parasuis SC1401 challenge. Bioinformatics analysis suggests that YfeA is highly conserved in G. parasuis, and its metal-binding sites have been strictly conserved throughout evolution. Stimulation of RAW 264.7 macrophages with YfeA verified that toll-like receptors (TLR) 2 and 4 participated in the positive transcription and expression of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α. The activation of TLR2 and TLR4 utilized the MyD88/MAL and TRIF/TRAM pairs to initiate TLRs signaling. Furthermore, YfeA was shown to stimulate nuclear translocation of NF-κB and activated diverse mitogen-activated protein (MAP) kinase signaling cascades, which are specific to the secretion of particular cytokine(s) in murine macrophages. Separate blocking TLR2, TLR4, MAPK, and RelA (p65) pathways significantly decreased YfeA-induced pro-inflammatory cytokine production. In addition, YfeA-stimulated RAW 264.7 produces the pro-inflammatory hallmark, reactive oxygen species (ROS). In conclusion, our findings indicate that YfeA is a novel pro-inflammatory mediator in G. parasuis and induces TLR2 and TLR4-dependent pro-inflammatory activity in RAW 264.7 macrophages through P38, JNK-MAPK, and NF-κB signaling pathways.

Immunomodulatory activity of Senegalia macrostachya (Reichenb. ex DC.) Kyal. & Boatwr seed polysaccharide fraction through the activation of the MAPK signaling pathway in RAW264.7 macrophages

Senegalia macrostachya (Reichenb. ex DC.) Kyal. & Boatwr seed (SMS) is a wild legume used as food and medicine in many African countries. In the current study, a novel polysaccharide (SMSP2) was extracted from SMS using hot water and purified with DEAE-52 cellulose. Its structure was characterized, and the immunomodulatory activity and possible molecular mechanism in murine macrophage RAW264.7 were explored. The results revealed that SMSP2 was a uronic acid-rich polysaccharide (51.6%, w/w) with a molecular weight of 52.07 kDa. The neutral sugars were mainly arabinose, xylose, mannose, and galactose at a molar ratio of 1.00 : 0.84 : 0.90 : 0.07. Interestingly, SMSP2 treatment markedly promoted macrophage proliferation and phagocytosis and induced the expression of inflammatory mediators, such as nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, and IL-10. SMSP2-induced macrophage stimulation occurs through the activation of the mitogen-activated protein kinase (MAPK) signaling pathway. Moreover, macrophage surface complement receptor 3 (CR3) might play an important role in SMSP2-induced macrophage activation. This study revealed that SMSP2 is a potent immunomodulator, which could be used as a functional food and a pharmaceutical adjuvant in treating immune-compromising diseases.

Ultrasonic-Assisted Extraction of Codonopsis pilosula Glucofructan: Optimization, Structure, and Immunoregulatory Activity

In recent years, multiple edible polysaccharides from Codonopsis pilosula were mainly isolated with high average molecular weights and exhibited various bioactivities, but it was proven that low-molecular-weight polysaccharides could exert stronger activities due to the superior water solubility and permeability. In the present study, the water-soluble polysaccharide C. pilosula with low molecular weight was isolated under ultrasonic assistance at 30 °C, the extraction process was optimized via response surface method (RSM), and the structure and immunoregulatory activity were further investigated. The maximum yield (4.86%) for crude polysaccharides (cCPPs) was obtained under following parameters: ultrasonic power of 370 W, liquid/material ratio of 33 mL/g, ultrasonic time of 81 min. Subsequently, the cCPPs were further purified through dialysis and Sephadex G-25 column to acquire purified polysaccharide (CPPs). Structural analysis indicated that CPPs was a glucofructan (average molecular weight of 4.23 × 10³ Da) with (2→1)-β-D-Fruf and (1→)-α-D-Glcp as the backbone branched by (2→6)-β-D-Fruf. Additionally, CPPs could enhance immunoregulatory function by stimulating NO production and cytokine (IL-6 and TNF-α) secretion of RAW264.7 macrophages dose-dependently, which presented no cytotoxic effects. These data suggest that CPPs have the potential to be used as a nutritional dietary compound and natural immunostimulant supplement in the food industry.

Immunomodulatory activity of egg yolk protein hydrolysates prepared by novel two-step hydrolysis: A study of mechanism and stability after in vitro digestion model

The aim of this study was to determine the immunomodulatory activity of 2-step egg yolk protein hydrolysates. A two-step hydrolysate of egg yolk protein was prepared using 2 enzymes sequentially, pancreatin and neutrase (EYPH-PN). Our results illustrated that EYPH-PN increased the expression of inducible nitric oxide synthase (iNOS) mRNA in macrophages, resulting in increased nitric oxide (NO) production. EYPH-PN could also enhance the production of tumor necrosis factor (TNF)-α and interleukin (IL)-6 at both the mRNA and protein levels in macrophages. In addition, treatment with EYPH-PN increased the phagocytic activity of macrophages. According to the evaluation with specific inhibitors, both p38 and JNK cell signaling pathways were involved in the activation of macrophages induced by EYPH-PN. As the TLR-2 receptor of macrophages was blocked, the NO production induced by EYPH-PN was decreased. These results suggest that EYPH-PN activates RAW 264.7 macrophages via the TLR-2/p38/JNK pathway to increase the production of NO, TNF-α, and IL-6, and increases phagocytic activity. Furthermore, the immunomodulatory activity of EYPH-PN was maintained even after applying the in vitro digestion model. Taken together, EYPH-PN could be used as a functional food ingredient with excellent immunomodulatory activity in the food industry. Therefore, this study suggests a new alternative method to effectively utilize egg yolk protein, a by-product of the poultry industry.

Understanding immune-modulatory efficacy in vitro

Boosting or suppressing our immune system represents an attractive adjunct in the treatment of infections including SARS-CoV-2, cancer, AIDS, malnutrition, age related problems and some inflammatory disorders. Thus, there has been a growing interest in exploring and developing novel drugs, natural or synthetic, that can manipulate our defence mechanism. Many of such studies, reported till date, have been designed to explore effect of the therapeutic on function of macrophages, being a key component in innate immune system. Indeed, RAW264.7, J774A.1, THP-1 and U937 cell lines act as ideal model systems for preliminary investigation and selection of dose for in vivo studies. Several bioassays have been standardized so far where many techniques require high throughput instruments, cost effective reagents and technical assistance that may hinder many scholars to perform a method demanding compilation of available protocols. In this review, we have taken an attempt for the first time to congregate commonly used in vitro immune-modulating techniques explaining their principles. The study detected that among about 40 different assays and more than 150 sets of primers, the methods of cell proliferation by MTT, phagocytosis by neutral red, NO detection by Griess reaction and estimation of expression of TLRs, COX-2, iNOS, TNF-α, IL-6 and IL-1β by PCR have been the most widely used to screen the therapeutics under investigation.

Structural characterization, and in vitro immunostimulatory and antitumor activity of an acid polysaccharide from Spirulina platensis

In this study, a novel heteropolysaccharide named SP90-1 with immunostimulatory and antitumor activity was purified and characterized from Spirulina platensis. SP90-1 has a molecular weight of 63.92 kDa and mainly consists of rhamnose (Rha), glucose (Glc), galactose (Gal) and glucuronic acid (GlcA), followed by the minor components Fuc and Xyl. The backbone of SP90-1 was determined to be →2)-α-d-Rhap-(1 → 2,3)-α-d-Rhap-(1 → 4)-β-d-Glcp-(1 → [3)-β-d-Rhap-(1→]₃, with branches at the O-3 of Rha, consisting of the side chains 4-Galp and 4-GlcpA. SP90-1 was found to significantly enhance phagocytic capacity, promote the secretion of nitric oxide (NO), interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) in RAW264.7 cells, and remarkably inhibit the growth of A549 lung cancer cells. These findings demonstrate that SP90-1 could potentially be further explored for immunomodulatory biomedical applications.

Enhanced γ-aminobutyric acid and sialic acid in fermented deer antler velvet and immune promoting effects

Deer antler velvet is widely used in traditional medicine for its anti-aging, antioxidant, and immunity-enhancing effects. However, few studies have reported on the discovery of probiotic strains for deer antler fermentation to increase functional ingredient absorption. This study evaluated the ability of probiotic lactic acid bacteria to enhance the concentrations of bioactive molecules (e.g., sialic acid and gamma-aminobutyric acid [GABA]) in extracts of deer antler velvet. Seventeen strains of Lactobacillus spp. that were isolated from kimchi and infant feces, including L. sakei, L. rhamnosus, L. brevis, and L. plantarum, and those that improved the life span of Caenorhabditis elegans were selected for evaluation. Of the 17 strains, 2 (L. rhamnosus LFR20-004 and L. sakei LFR20-007) were selected based on data showing that these strains increased both the sialic acid and GABA contents of deer antler extract after fermentation for 2 d and significantly improved the life span of C. elegans. Co-fermentation with both strains further increased the concentrations of sialic acid, GABA, and metabolites such as short-chain fatty acids and amino acids. We evaluated the biological effects of the fermented antler velvet (FAV) on the antibacterial immune response in C. elegans by assessing worm survival after pathogen infection. The survival of the C. elegans conditioned with FAV for 24 h was significantly higher compared with that of the control worm group fed only normal feed (non-pathogenic E. coli OP50) exposed to E. coli O157:H7, Salmonella typhi, and Listeria monocytogenes. To evaluate the protective effects of FAV on immune response, cyclophosphamide (Cy), an immune-suppressing agent was treated to in vitro and in vivo. We found that FAV significantly restored viability of mice splenocytes and immune promoting-related cytokines (interleukin [IL]-6, IL-10, inducible nitric oxide synthase [iNOS], interferon [IFN]-γ, and tumor necrosis factor [TNF]-α) were activated compared to non-fermented deer antlers. This finding indicated the protective effect of FAV against Cy-induced cell death and immunosuppressed mice. Taken together, our study suggests that immune-promoting antler velvet can be produced through fermentation using L. rhamnosus LFR20-004 and L. sakei LFR20-007.

Immunomodulatory effect of intracellular polysaccharide from mycelia of Agaricus bitorquis (QuéL.) Sacc. Chaidam by TLR4-mediated MyD88 dependent signaling pathway

Agaricus bitorquis (QuéL.) Sacc. Chaidam is a valuable edible fungus in Qinghai-Tibet plateau and ABSP is a novel intracellular polysaccharide from its mycelia. GC and NMR analysis determined ABSP is galactoglucomannan-like polysaccharide that may have immunomodulatory effect. This study used RAW264.7 as model cell to determine immunomodulatory effect of ABSP. After ABSP treatment, viability and phagocytic ability promoted, and NO, ROS, TNF-α levels also raised which proved ABSP had immune regulation to RAW264.7. WB and qRT-PCR determined the key proteins and genes expression of TLR4, MyD88, TRAF-6 and NF-κB significantly increased while protein and gene expression of TRAM had no significant increase. Also, TNF-α level extremely decreased by adding inhibitors of TLR4 and MyD88 which confirmed ABSP could immunologically regulate RAW264.7 byTLR4-MyD88 dependent pathway. This study would provide theoretical basis for further study on ABSP and be helpful for development of beneficial functionally foods and exploitation of this resource.