Se-enriched G. frondosa polysaccharide protects against immunosuppression in cyclophosphamide-induced mice via MAPKs signal transduction pathway

Immunomodulatory Effects of Polysaccharides from Porphyra haitanensis in Hydrocortisone-Induced Immunocompromised Mice

This study investigated the immunomodulatory effect of polysaccharides from Porphyra haitanensis (PHP) using a hydrocortisone-induced immunosuppressive model. Immunocompromised mice were treated with varying doses of PHP and the effects on macroscopic indicators, macrophage function, and both cellular and humoral immune functions were comprehensively assessed. The results showed that PHP significantly increased the body weight and indexes of the spleen and thymus, improved the disorder of blood cell populations, and enhanced macrophage activity. Furthermore, PHP improved T lymphocyte subtypes and differentiation and regulated the CD4+/CD8+ ratio. PHP also promoted the expression of T-Bet and GATA-3 while maintaining immune homeostasis, alongside promoting cytokine secretion. PHP facilitated the production of antibody-generating cells, serum hemolysin, and antibodies. Western blot results revealed that PHP activates the TLR4/NF-κB pathway. These findings suggested that PHP exerts immunomodulatory effects on both the innate and adaptive immune systems.

Metabolomics analysis of anaphylactoid reactions induced by Xueshuantong injection in normal and immunocompromised mice

Background

Xueshuantong injection (Lyophilized) (XSTI) is widely used to treat cardiovascular and cerebrovascular diseases. However, anaphylactoid reactions (ARs) are frequently reported as one of its side effects, and the mechanisms of ARs and their relationship with the different immune status are still not well understood.

Purpose

This article aims to examine the sensitizing effect of XSTI, explore the impact of normal and immunocompromised states on ARs, and analyze AR-related metabolic pathways by metabolomics.

Methods

An immunocompromised mouse model was established through intraperitoneal injection of cyclophosphamide (CTX). Normal and immunocompromised mice were then treated with normal saline (NS), histamine (HIS), and XSTI, respectively. Behavioral responses, auricle blue staining, and Evans blue (EB) exudation were used as indices to evaluate the sensitization of XSTI on both normal and immunocompromised mice. Subsequently, ARs models with different immune statuses were established, and validated by measuring four serum indicators using enzyme-linked immunosorbent assay (ELISA). Finally, LC-MS metabolomics analysis was performed on mouse serum to evaluate the metabolic pathways.

Results

The intensity of ARs induced by XSTI in mice was found to increase with the administered dose, with normal mice exhibiting higher AR intensities compared to immunocompromised mice. Metabolomic analysis revealed significant metabolic changes in XSTI-treated mice. The metabolic pathways predicted from these different metabolites include biotin metabolism, histidine metabolism, glycerolipid metabolism, bile secretion, arachidonic acid metabolism, sphingolipid metabolism, niacin and nicotinamide metabolism, tryptophan metabolism, steroid biosynthesis, and arginine and proline metabolism.

Conclusion

Research indicated that the sensitization of XSTI is dose-dependent, and mice with weakened immune functions exhibit lower sensitivity. Through metabolomics research, the differential metabolites in mice were analyzed, and the metabolic pathways inducing ARs were predicted. This study offers guidance on safe medication from the perspective of organism susceptibility and lays a foundation for research on the potential mechanisms of ARs.

Research progress of edible mushroom polysaccharide-metal trace element complexes

Metal trace elements are crucial for human health, and the complexes of edible mushroom polysaccharides with metal trace elements are currently a research hotspot in the field of food science. This article reviews the preparation methods, structural characterization, and physiological activities of edible mushroom polysaccharide-metal trace element complexes, including iron, selenium, and zinc. Research has shown that iron complexes obtained through Co-thermal synthesis of the FeCl3 method exhibit excellent antioxidant and anti-anemia functions; selenium complexes prepared via selenium-enriched cultivation significantly enhance immunological and anti-cancer properties; zinc complexes improve lipid-lowering, liver protection, and antioxidant capabilities. However, there is an imbalance in research among different metal elements, particularly with a high density of studies on selenium complexes. These studies provide a foundation for the future development of edible mushroom polysaccharide-metal trace element complexes.

Immunomodulation of exopolysaccharide produced by Lacticaseibacillus rhamnosus ZFM216 in cyclophosphamide-induced immunosuppressed mice by modulating gut microbiota

This study investigated the immunoregulatory activity of exopolysaccharides (EPS) produced by Lacticaseibacillus rhamnosus ZFM216 in immunosuppressed mice induced by cyclophosphamide (CTX). The results showed that EPS treatment effectively improved the body weight, immune organ index and splenic lymphocyte proliferation. EPS also mitigated the damage of immune organs, restored intestinal morphology, and regulated the levels of serum hemolysin and cytokines (e.g. TNF-α, INF-γ and IL-10). EPS promoted the release of NO, TNF-α, IL-1β, and IL-6 in RAW 264.7 cells, however, such effect was inhibited in the presence of inhibitors of TLR4 and MAPKs signaling pathways-related proteins, confirming that EPS achieved the immunomodulation by activating these two signaling pathways. Additionally, EPS, as a prebiotic, effectively improved the diversity of microbial communities, regulated the relative abundance of dominant microbial communities, restored CTX-induced gut microbiota dysbiosis, and promoted the production of short chain fatty acids (SCFAs) in the gut of mice. Thus, immunoregulatory effect of EPS could be attributed to its good ability to modulate the gut microbiota. EPS produced by L. rhamnosus ZFM216 has promising application as an ingredient of functional foods due to its potent probiotic effect.

Immunostimulatory activity of sea buckthorn polysaccharides via TLR2/4-mediated MAPK and NF-κB signaling pathways in vitro and in vivo

SP0.1-1, derived from Sea buckthorn (Hippophae rhamnoides L.), has been discovered to exhibit unique antioxidant activity. In this study, we investigated the immunomodulatory activity and mechanisms of SP0.1-1 on macrophage RAW 264.7 cells in vitro and immunosuppressive mice induced by cyclophosphamide in vivo. The results indicated SP0.1-1 strengthened the immune functions via promoting the proliferation of RAW264.7 cells and phagocytic activity, along with stimulating the release of NO, ROS and cytokines including TNF-α, IL-6, IL-1β and IFN-γ. Western blot and molecular docking analysis demonstrated that SP0.1-1 attached to the prime receptors TLR2 and TLR4 in RAW264.7 cells, and triggered the activation of MyD88-mediated MAPK and NF-κB signaling pathways, thereby exerting the immune response in RAW264.7 cells. However, the intervention of specific inhibitors against TLR2, TLR4, JNK, ERK, p38 and NF-κB blocked the TLR-mediated MAPK and NF-κB signaling pathways and downregulated the levels of NO and the aforementioned cytokines, thus suppressing the activation of macrophages. Therefore, it can be speculated that SP0.1-1 activated the macrophages principally via the TLR2/4-MyD88-mediated MAPK and NF-κB signaling pathways. Additionally, SP0.1-1 could protect against the cyclophosphamide-induced immunosuppression in mice, manifested by the improvement of body weight, immune organ indices, phagocytic index, and the relievement of spleen damage, along with the enhancement of cytokines TNF-α, IL-6, IFN-γ and immunoglobulin IgG and IgM. These findings will shed light on the molecular mechanism of SP0.1-1 on the immunoregulatory effect, and lay the foundation for exploiting a potential immunostimulatory agent of SP0.1-1.

Role of autonomic nervous system in BDE-209 maternal exposure induced immunotoxicity in female offspring

Decabrominated diphenyl ether (BDE-209) is a typical persistent organic pollutant that can cross the placental barrier, increasing the exposure risk for offspring. Norepinephrine (NE) from nerve terminals and acetylcholine (Ach) can bind to specific receptors on immune cells, inhibit the immune function of the body then cause immunotoxicity. However, whether maternal exposure to BDE-209 could lead to immunotoxicity in the offspring by acting on the sympathetic and parasympathetic nervous systems remains unclear. In view of this, the pregnancy and lactation rat BDE-209 exposure model was established and the results demonstrated that pregnancy and lactation BDE-209 exposure could induce immunotoxicity to female offspring via affecting immunopathology (hematological and biochemical parameters, organ indices, and spleen histopathological), decreasing humoral immunity (serum hemolysin, immunoglobulins, and cytokine productions), damaging cellular immunity (splenic lymphocytes and spleen cytokine productions), and restraining nonspecific immunity. Moreover, a dramatically significant correlation was observed between spleen nerve indices and immunity indices. Additionally, the mechanism revealed that maternal BDE-209 exposure caused offspring immunotoxicity through (1) activating MHC/PKCθ/NF-κB pathway; (2) promoting sympathetic nervous pathway, by upregulating the expression of β2AR protein, which in turn elevating cAMP, following activate PKA and phosphorylate CREB, ultimately leading to immunotoxicity;(3) activating parasympathetic nerve pathway by reducing the binding with Ach and α7nAchR, upregulating the expression of JAK2 and phosphorylating STAT3, induced immunotoxicity of female offspring.

An alkali-extracted neutral heteropolysaccharide from Phellinus nigricans used as an immunopotentiator in immunosuppressed mice by activating macrophages

A neutral heteropolysaccharide (PNANb) was isolated with alkali (0.1 M NaOH) from mycelia of Phellinus nigricans, and the structure, immunostimulating activity and some of the underlying molecular mechanisms of action of PNANb were explored in the current study. PNANb (14.95 kDa) predominantly consisted of Gal, Glc, and Man with minor Fuc. GC-MS and NMR analyses indicated that the backbone of PNANb was mainly composed of 6-α-Galp, 2,6-α-Galp with minor 3,6-β-Glcp, which was substituted with complex side chains at C-2 of 2,6-α-Galp and C-3 of 3,6-β-Glcp. Notably, PNANb (50 or 100 mg/kg) possessed immunoprotective effects in cyclophosphamide (Cy)-induced immunosuppressed C57BL/6 mice, which was supported by evidence including the enhancement of spleen and thymus indices, levels of serum immunoglobulins (IgG, IgM) and cytokines (IFN-γ, IL-2, IL-4, IL-10), and macrophage activity. However, the immunostimulation effects of PNANb were decreased when macrophages were depleted, underscoring the essential role of macrophages in the beneficial effects of PNANb in Cy-induced immunosuppressed mice. Further investigations in vitro indicated that PNANb activated macrophages through MAPK/NF-κB signaling pathways mediated by Toll-like receptor 4. Therefore, PNANb can serve as a prospective immunopotentiator in immunosuppression.

Peptidome comparison on the immune regulation effects of different casein fractions in a cyclophosphamide mouse model

The protein composition of human milk plays a crucial role in infant formula milk powder formulation. Notably, significant differences exist between bovine casein and human milk casein. Previous studies have shown that casein hydrolysates could enhance immune function; however, gastrointestinal dyspepsia in infants affects the type and function of peptides. Therefore, the present study used peptidomics to sequence and analyze hydrolyzed peptides from different casein fractions. Additionally, animal experiments were conducted to assess the functionality of these casein fractions and elucidate their differences. The results revealed variations in peptide composition among the different casein fractions of formula milk powder. Interestingly, milk powder formulated with both β- and κ-casein (BK) exhibited significant enrichment of peptides related to the immune system. Moreover, the BK group significantly alleviated immune organ damage in cyclophosphamide-treated mice and regulated serum levels of pro-inflammatory and anti-inflammatory factors. Furthermore, feeding different casein fractions influenced the intestinal microflora of cyclophosphamide-treated mice, with the BK group mitigating the changes caused by cyclophosphamide. In conclusion, the findings suggest that BK formula in milk powder has the potential to positively enhance immunity. This study provides a robust theoretical basis for human-emulsified formula milk powder development.

Research Progress of Selenium-Enriched Foods

Selenium is an essential micronutrient that plays a crucial role in maintaining human health. Selenium deficiency is seriously associated with various diseases such as Keshan disease, Kashin-Beck disease, cataracts, and others. Conversely, selenium supplementation has been found to have multiple effects, including antioxidant, anti-inflammatory, and anticancer functions. Compared with inorganic selenium, organic selenium exhibits higher bioactivities and a wider range of safe concentrations. Consequently, there has been a significant development of selenium-enriched foods which contain large amounts of organic selenium in order to improve human health. This review summarizes the physiological role and metabolism of selenium, the development of selenium-enriched foods, the physiological functions of selenium-enriched foods, and provides an analysis of total selenium and its species in selenium-enriched foods, with a view to laying the foundation for selenium-enriched food development.

Integrated multi-omics reveals the beneficial role of chlorogenic acid in improving the growth performance and immune function of immunologically stressed broilers

Intensive production can cause immunological stress in commercial broilers. Chlorogenic acid (CGA) regulates the intestinal microbiota, barrier function, and immune function in chickens. As complex interrelations regulate the dynamic interplay between gut microbiota, the host, and diverse health outcomes, the aim of this study was to elucidate the immunoregulatory mechanisms of CGA using multi-omics approaches. A total of 240 one-day-old male broilers were assigned to a 2 × 2 factorial design with 2 CGA levels (0 or 500 mg/kg) either with or without dexamethasone (DEX) injection for a 21-day experimental period. Therefore, there were 4 dietary treatments: control, DEX, CGA, and DEX + CGA, with 6 replicates per treatment. CGA supplementation improved (P < 0.05) growth performance, jejunal morphology, jejunal barrier function, and immune function in DEX-treated broilers. Moreover, in DEX + CGA-treated broilers, the increase in gut microbiome diversity (P < 0.05) was consistent with a change in taxonomic composition, especially in the Clostridiales vadin BB60_group. Additionally, the levels of short-chain fatty acids increased remarkably (P < 0.01) after CGA supplementation. This was consistent with the Kyoto Encyclopedia of Genes and Genomes analysis results that the "pyruvate fermentation to butanoate" pathway was more enriched (P < 0.01) in the DEX + CGA group than in the DEX group. Proteomics revealed that CGA treatment increased the expression of several health-promoting proteins, thymosin beta (TMSB4X) and legumain (LGMN), which were verified by multiple reaction monitoring. Metabolomics revealed that CGA treatment increased the expression of health-promoting metabolites (2,4-dihydroxy benzoic acid and homogentisic acid). Proteomic and metabolic analyses showed that CGA treatment regulated the peroxisome proliferator-activated receptor (PPAR) and mitogen-activated protein kinase (MAPK) pathways. Western blotting results support these findings. Pearson's correlation analyses showed correlations (P < 0.01) between altered immune function, jejunal barrier function, different microbiota, proteins, and metabolites parameters. Overall, our data indicate that CGA treatment increased growth performance and improved the immunological functions of DEX-treated broilers by regulating gut microbiota and the PPAR and MAPK pathways. The results offer novel insights into a CGA-mediated improvement in immune function and intestinal health.

Optimum Reaction Conditions for the Synthesis of Selenized Ornithogalum caudatum Ait. (Liliaceae) Polysaccharides and Measurement of Their Antioxidant Activity In Vivo

This study determined the optimum reaction conditions for synthesizing selenium-containing polysaccharides. Polysaccharide IIA (with the highest yield) from Ornithogalum caudatum Ait. (Liliaceae) (OCAPIIA) was extracted and purified. Then, three parameters were selected to optimize the synthesis of selenized OCAPIIA (Se-OCAPIIA) using the Box-Behnken design (BBD) and response surface methodology (RSM). The morphology of Se-OCAPIIA was analyzed by scanning electron microscopy (SEM). The characteristic peaks and the monosaccharide composition of Se-OCAPIIA were evaluated by Fourier-transform infrared spectroscopy and gas chromatography. A D-galactose-induced aging mouse model was established, and the in vivo antioxidant activity of Se-OCAPIIA was measured. The optimal conditions for the synthesis of Se-OCAPIIA were as follows: reaction temperature, 72.38 °C; Na2SeO3 to OCAPIIA mass ratio, 0.93 g/g; and reaction time, 8.05 h. The selenium content of Se-OCAPIIA obtained using the optimized process was 3.131 ± 0.090 mg/g, close to the maximum predicted value (3.152 mg/g). Se-OCAPIIA contained D-mannose, D-glucose, and D-galactose at a molar ratio of 1.00:0.34:0.88. SEM showed that Se-OCAPIIA was spherical and flocculated. Compared with OCAPIIA, Se-OCAPIIA exhibited two characteristic peaks at 833 and 610 cm-1 in the infrared spectrum. Se-OCAPIIA increased catalase, glutathione peroxidase, and superoxide dismutase activities and decreased MDA concentrations in the mouse liver. Moreover, Se-OCAPIIA treatment improved liver morphology, decreased the levels of IL-1β and IL-6, and increased IL-10 concentration. In conclusion, the synthesis of Se-OCAPIIA is effective, simple, and feasible. Se-OCAPIIA demonstrated high antioxidant activity in vivo and is a promising antioxidant and therapeutic agent.

Immunomodulatory activity of semen Ziziphi Spinosae protein: a potential plant protein functional food raw material

Semen Ziziphi Spinosae protein (SZSP) is a new plant protein resource with good food functional properties and health care function. However, the biological activity of SZSP has not been further studied, which greatly limits the development and utilization of SZSP in the food industry. The aim of this study was to investigate the protective effect of SZSP on immunosuppressed mice and its inhibitory effect on immune-stimulated RAW264.7 cells. The results demonstrated that SZSP remarkably improved the immunomodulatory secretion in serum (interleukin-2, tumor necrosis factor-α [TNF-α], interferon-γ, immunoglobulin-A, immunoglobulin-G, immunoglobulin-M) and primary macrophages (nitric oxide, interleukin-1β, TNF-α) and promoted the NK-cell killing activity of primary splenocytes in CTX-induced immunosuppression mice. Immunohistochemical analysis results indicated that the secretion of CD₄⁺ and CD₈⁺ in the spleen and thymus can be regulated by SZSP, leading to inhibition of the damage induced by cyclophosphamide in mice. Meanwhile, in order to clarify the immunomodulatory mechanism of SZSP, we showed that SZSP significantly inhibited the secretion of NO, interleukin-6, and TNF-α and reduced the phosphorylation expression of p-ERK, p-JNK, and p-IκBα in lipopolysaccharide-stimulated RAW264.7 cells. Therefore, the immunomodulatory effect of SZSP may be related to the activation of MAPKs and NF-κB signaling pathways. Based on the above studies, the preliminary purification of SZSP was continued, and S1F2G1 with immunomodulatory activity was obtained. Taken together, SZSP has an immunoregulatory effect in vivo and in vitro and may be a favorable candidate of functional food raw material for regulating immune responses.

A Se-enriched Grifola frondosa polysaccharide induces macrophage activation by TLR4-mediated MAPK signaling pathway

Se-polysaccharide (Se-GFP-22) from Se-enriched Grifola frondosa has double and cooperative activities of polysaccharide and Se. To delineate the underlying mechanism and signaling cascade involved in immune-stimulatory property of Se-GFP-22, the production of cellular mediators and key proteins in signaling pathway was examined. Results showed that Se-GFP-22 exhibited no cytotoxic and had a high capacity to promote macrophage phagocytosis, up-regulate interleukin-2 (IL-2), tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), and nitric oxide (NO) productions, as well as the relative messenger RNA (mRNA) expressions. In Se-GFP-22-induced macrophages, intracellular superoxide dismutase (SOD) activity was significantly increased to protect cells from oxidative injury. However, Se-GFP-22 induced macrophage activation was suppressed when the toll-like receptor 4 (TLR4) signaling pathway was blocked by a specific TLR4 inhibitor. According to the western blot analysis and the use of specific inhibitors against the mitogen-activated protein kinases (MAPK) signaling pathway, we speculated that Se-GFP-22 activated RAW264.7 macrophages through the TLR4-mediated MAPK signaling pathway. This study provides a molecular basis for the potential of Se-GFP-22 as a novel immune-stimulatory agent.

Chimonanthus nitens Oliv Polysaccharides Modulate Immunity and Gut Microbiota in Immunocompromised Mice

To investigate the immunomodulatory activities of Chimonanthus nitens Oliv polysaccharides (COP1), an immunosuppressive mouse model was generated by cyclophosphamide (CY) administration and then treated with COP1. The results demonstrated that COP1 ameliorated the body weight and immune organ (spleen and thymus) index of mice and improved the pathological changes of the spleen and ileum induced by CY. COP1 strongly stimulated the production of inflammatory cytokines (IL-10, IL-12, IL-17, IL-1β, and TNF-α) of the spleen and ileum by promoting the mRNA expressions. Furthermore, COP1 had immunomodulatory activity by increasing several transcription factors (JNK, ERK, and P38) in the mitogen-activated protein kinase (MAPK) signaling pathway. Related to the above immune stimulatory effects, COP1 positively affected the production of short-chain fatty acids (SCFAs) and the expression of ileum tight junction (TJ) protein (ZO-1, Occludin-1, and Claudin-1), upregulated the level of secretory immunoglobulin A (SIgA) in the ileum and microbiota diversity and composition, and improved intestinal barrier function. This study suggests that COP1 may provide an alternative strategy for alleviating chemotherapy-induced immunosuppression.

Selenium-enriched plant foods: Selenium accumulation, speciation, and health functionality

Selenium (Se) is an essential element for maintaining human health. The biological effects and toxicity of Se compounds in humans are related to their chemical forms and consumption doses. In general, organic Se species, including selenoamino acids such as selenomethionine (SeMet), selenocystine (SeCys₂), and Se-methylselenocysteine (MSC), could provide greater bioactivities with less toxicity compared to those inorganics including selenite (Se IV) and selenate (Se VI). Plants are vital sources of organic Se because they can accumulate inorganic Se or metabolites and store them as organic Se forms. Therefore, Se-enriched plants could be applied as human food to reduce deficiency problems and deliver health benefits. This review describes the recent studies on the enrichment of Se-containing plants in particular Se accumulation and speciation, their functional properties related to human health, and future perspectives for developing Se-enriched foods. Generally, Se's concentration and chemical forms in plants are determined by the accumulation ability of plant species. Brassica family and cereal grains have excessive accumulation capacity and store major organic Se compounds in their cells compared to other plants. The biological properties of Se-enriched plants, including antioxidant, anti-diabetes, and anticancer activities, have significantly presented in both in vitro cell culture models and in vivo animal assays. Comparatively, fewer human clinical trials are available. Scientific investigations on the functional health properties of Se-enriched edible plants in humans are essential to achieve in-depth information supporting the value of Se-enriched food to humans.

Heterogalactan WPEP-N-b from Pleurotus eryngii enhances immunity in immunocompromised mice

This study reports on in vivo immunomodulatory activities mediated by WPEP-N-b, a heterogalactan from Pleurotus eryngii. Using cyclophosphamide (CTX)-induced immunosuppressed mice, we demonstrate here that WPEP-N-b enhances immunity as determined by the immune organ index, peripheral blood immune cell content, splenocyte proliferation, NK cell activity and T lymphocyte subpopulations. WPEP-N-b prevented apoptosis of bone marrow cells induced by CTX. The level of cytokines (i.e. TNF-α, IL-6 and IL-1β) and macrophage activity in these immunocompromised mice were restored upon treated with WPEP-N-b. Mechanistically, it appears that WPEP-N-b enhances splenocyte proliferation and NK cell activity might through the Toll-like receptor 4 (TLR4)-PKC signaling axis, and increases macrophage activity by activating JNK, p38 and NF-κB signaling pathways and Toll-like receptor 2 (TLR2) is the possible receptor of WPEP-N-b in macrophages. Our findings indicate that WPEP-N-b may function as a natural immune stimulant.

Immune-Enhancing Effect of Heat-Treated Levilactobacillus brevis KU15159 in RAW 264.7 Cells

Probiotics are alive microbes that present beneficial to the human's health. They influence immune responses through stimulating antibody production, activating T cells, and altering cytokine expression. The probiotic characteristics of Levilactobacillus brevis KU15159 were evaluated on the tolerance and adherence to gastrointestinal conditions. L. brevis KU15159 was safe in a view of producing various useful enzymes and antibiotic sensitivity. Heat-treated L. brevis KU15159 increased production of nitric oxide (NO) and phagocytic activity in RAW 264.7 cells. In addition, heat-treated L. brevis KU15159 upregulated the expression of inducible nitric oxide synthase (iNOS) and proinflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6, at protein as well as mRNA levels. In addition, the mitogen-activated protein kinase (MAPK) pathway, which regulates the immune system, was activated by heat-treated L. brevis KU15159. Therefore, L. brevis KU15159 exhibited an immune-enhancing effect by the MAPK pathway in macrophage.

Selenium-Containing Agents Acting on Cancer-A New Hope?

Selenium-containing agents are more and more considered as an innovative potential treatment option for cancer. Light is shed not only on the considerable advancements made in understanding the complex biology and chemistry related to selenium-containing small molecules but also on Se-nanoparticles. Numerous Se-containing agents have been widely investigated in recent years in cancer therapy in relation to tumour development and dissemination, drug delivery, multidrug resistance (MDR) and immune system-related (anti)cancer effects. Despite numerous efforts, Se-agents apart from selenocysteine and selenomethionine have not yet reached clinical trials for cancer therapy. The purpose of this review is to provide a concise critical overview of the current state of the art in the development of highly potent target-specific Se-containing agents.

Antitumor effects of polysaccharides from Tetrastigma hemsleyanum Diels et Gilg via regulation of intestinal flora and enhancing immunomodulatory effects in vivo

Tetrastigma hemsleyanum Diels et Gilg is a traditional Chinese herbal medicine with high medicinal value, and antitumor, antioxidant and anti-inflammatory biological activities. However, while several studies have focused on flavonoids in Tetrastigma hemsleyanum tubers, there are few studies on the enhanced immune effect of Tetrastigma hemsleyanum polysaccharides (THP). In this study, we evaluated the antitumor effect of THP in a lung tumor model and explored the mechanism of antitumor activity through intestinal flora. In addition, a cyclophosphamide (CTX)-induced immunosuppression model was used to declare the immunomodulatory effect of THP in the immunosuppressive state induced by antitumor drugs. The results showed that THP increased the content of ileum secreted immunoglobulin A (SIgA) and cecum short-chain fatty acids (SCFAs) and improved microbial community diversity, regulating the relative abundance of dominant microbiota flora from the phylum level to the genus level, and recovering the intestinal microflora disorder caused by tumors. Additionally, THP can increase the organ indices and improve immune organ atrophy. THP can upregulate routine blood counts and stimulate the production of the serum cytokines. THP also promoted the macrophage phagocytic index, NK-cell activation, and complement and immunoglobulin (IgG, IgA, IgM) levels. The detection of Splenic lymphocyte proliferation and T lymphocyte subsets also sideways reflects that THP can restore CTX-induced immune inhibition in mice. In conclusion, this study suggests that THP can effectively achieve the enhanced antitumor effects, regulate gut microbiota and improve the immunosuppression induced by antitumor drugs. Therefore, THP can enhance the immune capacity and provide novel immunomodulatory and antineoplastic adjuvant agents.

rhCNB Improves Cyclophosphamide-Induced Immunodeficiency in BALB/c Mice

Background

This study aims to explore the immunomodulatory effect of rhCNB on mice with cyclophosphamide (CTX)-induced immunodeficiency through TLR₄/MAPK pathway.

Methods

BALB/c mice were randomly divided into three groups: a negative control group, an immunosuppression model group, and a rhCNB treatment group. Tail vein injection of cyclophosphamide (40 mg/kg) was used to establish a mouse immunosuppression model. Intraperitoneal injection of rhCNB (20 mg/kg) was administered to the treatment group, whereas equal quantities of normal saline were given to the control group and model group. Perform peripheral blood routine of CD4, CD8, and CD19 lymphocyte subsets and peripheral blood Th1/Th2 cell subsets 24 hours after the last administration. RT-PCR was used to detect mRNA levels of TLR₄, P38, JNK, T-bet, and GATA₃, the spleen immune organ index was measured, and the histopathological status of the spleen and thymus was observed.

Results

The results showed that compared with the control group, WBC, PLT, LYM, NEU, immune organ index, CD4⁺/CD8⁺ and CD19⁺ subgroup ratio, and peripheral blood Th1/Th2 cell subgroups decreased in the model group. The mRNA levels of TLR₄, P38, JNK, T-bet, and GATA₃ decreased compared with the model group, while they increased in the treatment group.

Conclusions

rhCNB has an immunomodulatory effect by regulating the expression of Th1/Th2 cytokine balance through the TLR₄/MAPK signaling pathway and promoting the differentiation and proliferation of lymphocytes, thereby improving the immune function.

Screening of Codonopsis radix Polysaccharides with Different Molecular Weights and Evaluation of Their Immunomodulatory Activity In Vitro and In Vivo

Polysaccharide is one of the main components of Codonopsis radix (CR) and has good immune activity. However, the immune activity of CR polysaccharides with different molecular weights has not been systematically screened. In this study, the polysaccharides of CR from Pingshun of Shanxi Province (PSDSs) were first divided into two groups using ultrafiltration: 3.3 kDa (PSDSs-1) and more than 2000 kDa (PSDSs-2). The immunomodulatory effects of PSDSs with different molecular weights were evaluated in vitro and in vivo. In vitro experimental results showed that compared with Lipopolysaccharide-induced macrophages, PSDSs-1 increased TNF-α and IL-6 levels and decreased IL-10. Meanwhile, PSDSs-2 showed the opposite effect, indicating the difference in pro- and anti-inflammatory activities of PSDSs with different molecular weights. The immunosuppressive model of cyclophosphamide proved that PSDSs have immune-promoting function, with PSDSs-1 exhibiting a better effect than PSDSs-2. In vitro and in vivo experiments illustrated the complexity of PSDS immunomodulation. Further research on the functions of PSDs with different molecular weights is needed to lay a foundation for their classification and application.

Phytochemical composition, antioxidant activities and immunomodulatory effects of pigment extracts from Wugong Mountain purple red rice bran

The study was to investigate the phytochemical composition, antioxidant activities and the immunomodulatory effects on cyclophosphamide-induced (cy-induced) immunosuppressed mice of purple red rice bran pigment extracts (PRBP). The phytochemical composition of total anthocyanins, total phenolic and total flavonoid contents were evaluated. Moreover, UV-Vis, FT-IR and UPLC-ESI-QTOF-MS spectra analysis identified for the first time the presence of seventeen anthocyanins in PRBP, including five anthocyanin aglycones and twelve acetylated anthocyanins, suggesting that PRBP were a highly acylated anthocyanin profile. The DPPH, ABTS⁺, hydroxyl radical scavenging activity and FRAP assays showed that PRBP had excellent antioxidant activities. Further, the results of animal experiments showed that PRBP alleviated immune organ damage and recovered damaged immune function, such as preventing the reduction of body weight, spleen and thymus organ indexes, and significantly increasing the levels of TNF-α, IL-6 and IL-1β in spleen which indicated that PRBP alleviated immunosuppression in Cy-induced mice. The immunomodulatory activity of PRBP was reflected by the upregulation of MAPK signaling pathways after gavage. Taken together, these results suggest that PRBP possessed a certain antioxidant and immunomodulatory abilities. These findings will lead to a better understanding of the biological properties of PRBP and broaden its utilization in food processing.

Safety Assessment of Canola Oil Extracted by Aid of Pulsed Electric Field: Genetic, Acute and Subacute Toxicity

Pulsed electric field (PEF) is a nonthermal technology resulting in the rupture of cell membranes and increasing the electrical conductivity and the permeability of intracellular material. There was little work about the safety of food treated by PEF. The acute, subacute oral, and genetic toxicities were investigated to explore the safety of canola oil extracted by aid of PEF treatment (PTCO). The results showed that no negative consequences were caused by PEF. PTCO was regarded as practically non-toxic with a LD₅₀ higher than 40 g/kg bw. No oil intake-related mortality, clinical, weight gain and organ coefficient abnormalities were observed. The histopathological symptoms indicated a mild load but not obvious toxicities on liver and kidney. The 28-day subacute toxicity test confirmed that less than 10 g/kg·d bw of oil intake did not exhibit any intake-related changes in physical, physiological, biochemical, hematological, and histopathological signs. The less than 4 of atherosclerosis index suggested that no risk of cardiovascular disease caused by PTCO intake. It was speculated that the PEF treatment would not cause any safety issues to food products.

Purification and characterization of Se-enriched Grifola frondosa glycoprotein, and evaluating its amelioration effect on As3+ -induced immune toxicity

BACKGROUND

Selenium (Se)-enriched glycoproteins have been a research highlight for the role of both Se and glycoproteins in immunoregulation. Arsenic (As) is a toxicant that is potentially toxic to the immune function and consequently to human health. Several reports suggested that Se could reduce the toxicity of heavy metals. Moreover, more and more nutrients in food had been applied to relieve As-induced toxicity. Hence glycoproteins were isolated and purified from Se-enriched Grifola frondosa, and their preliminary characteristics as well as amelioration effect and mechanism on As³⁺ -induced immune toxicity were evaluated.

RESULTS

Four factions, namely Se-GPr11 (electrophoresis analysis exhibited one band: 14.32 kDa), Se-GPr22 (two bands: 20.57 and 31.12 kDa), Se-GPr33 (three bands: 15.08, 20.57 and 32.78 kDa) and Se-GPr44 (three bands: 16.73, 32.78 and 42.46 kDa), were obtained from Se-enriched G. frondosa via DEAE-52 and Sephacryl S-400 column. In addition, Se-GPr11 and Se-GPr44 are ideal proteins that contain high amounts of almost all essential amino acids. Thereafter, the RAW264.7 macrophage model was adopted to estimate the effect of Se-GPr11 and Se-GPr44 on As³⁺ -induced immune toxicity. The results showed that the pre-intervention method was the best consequent and the potential mechanisms were, first, by improving the oxidative stress state (enhancing the activity of superoxide dismutase and glutathione peroxidase, decreasing the levels of reactive oxygen species and malondialdehyde); secondly, through nuclear factor-κB and mitogen-activated protein kinase-mediated upregulation cytokines (interleukin-2 and interferon-γ) secretion induced by As³⁺ .

CONCLUSION

The results suggested Se-enriched G. frondosa may be a feasible supplement to improve health level of the As³⁺ pollution population. © 2021 Society of Chemical Industry.

Polysaccharides from Spores of Cordyceps cicadae Protect against Cyclophosphamide-Induced Immunosuppression and Oxidative Stress in Mice

This study investigated the purification, preliminary structure and in vivo immunomodulatory activities of polysaccharides from the spores of Cordyceps cicadae (CCSP). The crude CCSP was purified by diethylaminoethyl (DEAE)-cellulose and Sephadex G-100 chromatography, affording CCSP-1, CCSP-2 and CCSP-3 with molecular weights of 1.79 × 10⁶, 5.74 × 10⁴ and 7.93 × 10³ Da, respectively. CCSP-2 consisted of mannose and glucose, while CCSP-1 and CCSP-3 are composed of three and four monosaccharides with different molar ratios, respectively. CCSP-2 exhibited its ameliorative effects in cyclophosphamide-induced immunosuppressed mice through significantly increasing spleen and thymus indices, enhancing macrophage phagocytic activity, stimulating splenocyte proliferation, improving natural killer (NK) cytotoxicity, improving bone marrow suppression, regulating the secretion of cytokines and immunoglobulins, and modulating antioxidant enzyme system. These results indicate that CCSP-2 might be exploited as a promising natural immunomodulator.

Structural characterisation and bioactivity of polysaccharides isolated from fermented Dendrobium officinale

BACKGROUND

A polysaccharide was purified in this study, which was acquired from the fermentation broth of Dendrobium officinale Kimura et Migo. We aimed to investigate the structural features and bioactivity of this polysaccharide.

RESULTS

The polysaccharide was purified and the main polysaccharide fraction (i.e., DOP-1) was obtained. High-performance gel permeation chromatography (HPGPC) revealed that the molecular weight of DOP-1 was 447.48 kDa. Galactose, glucose and mannose were found to be present in DOP-1 via monosaccharide composition analysis, at a ratio of 1:1.79:6.71. Methylation and nuclear magnetic resonance spectroscopic analysis indicated that the backbone of DOP-1 was →4)-α-d-Glcp-(1 → 4)-α-d-Manp-(1 → 4)-α-d-Manp-(1 → 4,6)-α-d-Manp-(1→, and its repeating units were also preliminarily established. In vitro tests proved that DOP-1 not only protects RAW264.7 macrophages from the cytotoxic effect induced by lipopolysaccharide (LPS), but also inhibits cytokines (i.e., interleukin-6 and tumour necrosis factor-α) induced by LPS. DOP-1 demonstrated good scavenging activity in vitro toward 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radicals, as well as good metal chelating activity. Therefore, DOP-1 has potential antioxidant applications.

CONCLUSION

The structural characteristics of DOP-1 support its favourable biological activities and lay a strong foundation for further exploration of its structure-activity relationships and activity development, providing experimental data for the development and utilisation of fermentation broth of D. officinale. © 2021 Society of Chemical Industry.

Structure and pro-inflammatory activities of bran polysaccharides from a novel wheat kernel

In this study, the structure and pro-inflammatory activities of water-soluble wheat bran polysaccharides (WBP) were evaluated. WBP were heteropolysaccharides consisting 60.34% arabinoxylan as the main component and 31.80% mannose residues characterized with the instrumental analyses. The result of cellular experiment displayed that WBP had significant pro-inflammatory activities by increasing the concentration of nitric oxide (NO) and up-regulating the inflammatory cytokine expressions of inducible nitric oxide synthase (iNOS), interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2), and tumor necrosis factor-α (TNF-α). WBP mediated macrophages RAW 264.7 pro-inflammatory response through phosphatidylinositol 3 hydroxykinase/protein kinase B (PI3K/Akt) signaling pathway by significantly promoting Akt and phosphoinositide-dependent kinase 1 (PDK1) phosphorylations. Meanwhile, the expression of related phosphorylated proteins JNK and ERK1/2 was significantly up-regulated which suggested that WBP played pro-inflammatory roles by activating mitogen-activated protein kinases (MAPKs) signaling pathway. PRACTICAL APPLICATIONS: In recent years, wheat bran generally has the phenomenon of high yield and low utilization rate. Wheat bran has rich nutritional value and contains a lot of effective biologically active substances. Based on our findings, the water-soluble polysaccharides extracted from wheat bran have significant effects on regulating immunity and can be utilized as sources of natural immune modulators. The research can develop new functions of wheat bran polysaccharides, and improve processing utilization rate and product added value.

Immunomodulatory effects of selenium-enriched peptides from soybean in cyclophosphamide-induced immunosuppressed mice

In this study, selenium-enriched soybean peptides (<3 kDa, named Se-SPep) was isolated and purified from the selenium-enriched soybean protein (Se-SPro) hydrolysate by ultrafiltration. The in-vivo immunomodulatory effects of Se-SPep were investigated in cyclophosphamide-induced immunosuppressed mice. Se-SPep treatment could alleviate the atrophy of immune organs and weight loss observed in immunosuppressive mice. Besides, Se-SPep administration could dramatically improve total protein, albumin, white blood cell, immunoglobulin (Ig) M, IgG, and IgA levels in blood. Moreover, Se-SPep strongly stimulated interleukin-2 (IL-2), interferon-gamma (IFN-γ), nitric oxide (NO), and cyclic guanosine monophosphate productions by up-regulating mRNA expressions of IL-2, IFN-γ, and inducible NO synthase in spleen tissue. Furthermore, Se-SPep exhibits more effective immunomodulatory activity compared to Se-SPro and SPep. In conclusion, Se-SPep could effectively enhance the immune capacity of immunosuppressive mice. These findings confirm Se-SPep is an effective immunomodulator with potential application in functional foods or dietary supplements.

Synthesis, Characterization, Immune Regulation, and Antioxidative Assessment of Yeast-Derived Selenium Nanoparticles in Cyclophosphamide-Induced Rats

This article introduces an environmentally friendly and more economical method for preparing red selenium nanoparticles (Se-NPs) with high stability, good biocompatibility, and narrow size using yeast as a bio-reducing agent with high antioxidant, immune regulation, and low toxicity than inorganic and organic Se. The yeast-derived Se-NPs were characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The results revealed spherical-shaped particles of Se-NPs with an average diameter of 71.14 ± 18.17 nm, an amorphous structure, and surface enhancement with an organic shell layer, that provide precise geometry and stability in the formation of bio-inert gray or black Se-NPs instead of red Se-NPs. Furthermore, the addition of 0.3-0.8 mg/kg Se-NPs in the feed significantly improved the health of mice. As Se-NPs stimulated the oxidative state of mice, it significantly increased the level of GSH-Px, SOD, and AOC, and decreased the level of MDA. The yeast-derived Se-NPs alleviated the immunosuppression induced by cyclophosphamide, whereas protected the liver, spleen, and kidney of mice, stimulated the humoral immune potential of the mice, and significantly increased the levels of I g M, IgA, and I g G. These results indicated that the yeast-derived Se-NPs, as a trace element feed additive, increased the defense of the animal against oxidative stress and infectious diseases and therefore Se-NPs can be used as a potential antibiotic substitute for animal husbandry.

Beneficial Effects of Holothuria leucospilota Polysaccharides on Fermentability In Vivo and In Vitro

This work aimed to investigate the in-vitro and in-vivo fermentation behaviors of Holothuria leucospilota Polysaccharides (HLP) and the impact on mouse liver antioxidant activity. HLP showed excellent fermentability during in vitro experiments, which was characterized by increased levels of total sugar consumption and short-chain fatty acids (SCFAs). During in vitro fecal fermentation, the fucose contents in the HLP fermentation products (0.174 mg/mL) were higher than those of xylose and galactosamine during the first three hours, and fucose disappeared after 24 h. The concentrations of the generated SCFAs increased to 111.13 mmol/mL after in-vitro fermentation at 48 h. After 28 days of oral administration, the SCFA contents that were detected in the feces of mice treated with high HLP doses were significantly higher than those in the feces of mice treated with lower doses and the normal group. In addition, histological observations demonstrated that HLP increased the number of goblet cells without causing hepatocellular injury. Moreover, the increased glutathione peroxidase (GSH-Px) and superoxidase dismutase (SOD) activities and decreased malondialdehyde (MDA) contents in the mouse livers treated with HLP suggested the good performance of HLP with respect to liver antioxidants.

The immunoenhancement effects of sea buckthorn pulp oil in cyclophosphamide-induced immunosuppressed mice

In this study, the immunomodulatory effect of sea buckthorn (SBT) pulp oil was elucidated in immunosuppressed Balb/c mice induced by cyclophosphamide (CTX). The results showed that SBT pulp oil could reverse the decreasing trend of body weight, thymus/spleen index and hematological parameters induced by CTX. Compared with immunosuppressive mice induced by CTX, SBT pulp oil could enhance NK cytotoxicity, macrophage phagocytosis, and T lymphocyte proliferation, and regulate the proportion of T cell subsets in mesenteric lymph nodes (MLN), and promote the production of secretory immunoglobulin A (sIgA), IFN-γ, IL-2, IL-4, IL-12 and TNF-α in the intestines. In addition, SBT pulp oil can promote the production of short fatty acids (SCFAs), increase the diversity of gut microbiota, improve the composition of intestinal flora, increase the abundance of Alistipes, Bacteroides, Anaerotruncus, Lactobacillus, ASF356, and Roseburia, while decreasing the abundance of Mucispirillum, Anaeroplasma, Pelagibacterium, Brevundimonas, Ochrobactrum, Acinetobacter, Ruminiclostridium, Blautia, Ruminiclostridium, Oscillibacter, and Faecalibaculum. This study shows that SBT pulp oil can regulate the diversity and composition of intestinal microflora in CTX-induced immunosuppressive Balb/c mice, thus enhancing the intestinal mucosa and systemic immune response. The results can provide a basis for understanding the function of SBT pulp oil and its application as a new probiotic and immunomodulator.

Structural characterization and immunomodulatory mechanisms of two novel glucans from Morchella importuna fruiting bodies

Two novel glucans named MIPB50-W and MIPB50-S-1 were obtained from edible Morchella importuna with molecular weights (M_w) of 939.2 kDa and 444.5 kDa, respectively. MIPB50-W has a backbone of α-(1 → 4)-d-glucan, which was substituted at O-6 position by α-d-Glcp-(1→. Moreover, MIPB50-S-1 has a backbone of α-(1 → 4)-d-glucan, which was substituted at O-6 position by α-d-Glcp-(1 → 6)-α-d-Glcp-(1→. This is the first report about glucan found in Morchella mushrooms. Furthermore, MIPB50-W and MIPB50-S-1 strengthened the phagocytosis function and the promoted secretion of interleukins (IL)-6/tumor necrosis factor-alpha (TNF-α) and nitric oxide (NO), which induced the activation of Toll-like receptor 2 (TLR2), TLR4 as well as mitogen activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) pathways. Interestingly, MIPB50-S-1 performed the better immunomodulatory activity than that of MIPB50-W in almost all tests. Therefore, MIPB50-W and MIPB50-S-1 are potential immune-enhancing components of functional foods.

Structural characterization of a novel Schisandra polysaccharides and nutritional intervention in immunotoxicity to PCBs

A new polysaccharide from fruits of Schisandra chinensis (SCPP22) with a molecular weight of 143 ± 0.13 KDa was mainly made up of glucose and galactose. The possible structure of SCPP22 was showed that its main chain was composed of 1,4-α-d-Glup and branch was stretched from O-6 position of 1,4-β-d-Glup. Branches consisted of T-α-d-Galp. Further, SCPP22 could reverse PCB126-induced immunosuppression, significantly enhance body weight and immune organ indices. It also significantly ameliorated oxidative injury to immune organ induced by PCB126, as shown by evaluation of SOD activities, as well as MDA levels in spleen and thymus. SCPP22 strongly stimulated cytokines production by up-regulating mRNA expression of TNF-α, INF-γ and IL-2. Mechanism investigation revealed that recovery effects of SCPP22 in immunosuppression induced by PCB126 are mainly through regulating apoptosis-related proteins expression. Schisandra polysaccharides might be applied in functional food as nutritional intervention ingredient.

The immunomodulatory effects of Carapax Trionycis ultrafine powder on cyclophosphamide-induced immunosuppression in Balb/c mice

BACKGROUND

There are abundant resources of Carapax Trionycis from soft-shelled turtle processing wastes each year in China. Our preliminary work showed that Carapax Trionycis ultrafine powder (CTUP) obtained using ball-milling with a particle size of 2.24 μm (D0.025) contained more active ingredients. The CTUP D0.025 has a good bioaccessibility, but there has been no report about the immunomodulatory function of CTUP. Therefore, using a cyclophosphamide-induced immunosuppression mice model, we investigated the immunomodulatory effects of CTUP D0.025.

RESULTS

The results indicated that CTUP D0.025 administration significantly improved the immune organ (bone marrow, thymus and spleen) indices, ameliorated spleen tissue morphology and increased the capacity of splenocyte proliferation and the activity of macrophage phagocytosis. CTUP D0.025 also significantly promoted the secretion of cytokines (IL-2, IL-4, IL-10, IFN-γ and TNF-α), improved the related mRNA expression levels of IL2, IFN-γ, T-bet and GATA3 in immunosuppressed mice and increased the production of serum hemolysin and the levels of IgG, IgM as well as complement C₃ . Moreover, CTUP D0.025 administration enhanced the antioxidant capacity of mice, exhibited a moderating effect on the damage of bone and skeletal muscle and improved the recovery of bone mineral density and calcium metabolism.

CONCLUSIONS

These findings demonstrated that CTUP D0.025 had an effective immune-enhancing function in immunosuppressive Balb/c mice and also exhibited anti-osteoporosis properties. © 2020 Society of Chemical Industry.

Triptolide reduces salivary gland damage in a non-obese diabetic mice model of Sjögren's syndrome via JAK/STAT and NF-κB signaling pathways

Triptolide (TP) has anti-inflammatory and immunosuppressive effects. However, the effect of triptolide on Sjögren's syndrome (SS) is rarely reported. In this paper, we studied the effects of triptolide on non-obese diabetes mice model of SS. In this study, salivary flow rate was measured every two weeks, and autoantibodies levels in the serum were detected. Salivary gland index and spleen index were detected, pathological changes of salivary gland were detected by hematoxylin-eosin staining, inflammatory factors were detected by enzyme linked immunosorbent assay, lymphocytes were detected by flow cytometry, proliferation of T cells and B cells were detected, and related proteins were detected by Western blot. Triptolide increased salivary flow rate and salivary gland index, and decreased spleen gland index. Moreover, triptolide reduced the infiltration of lymphocytes to salivary glands, decreased the level of autoantibodies in serum, and reduced the inflammatory factors in salivary glands and IFN-γ induced salivary gland epithelial cells. Further, triptolide inhibited activator of JAK/STAT pathway and NF-κB pathway. In conclusion, triptolide could inhibit the infiltration of lymphocytes and the expression of inflammatory factors through JAK/STAT pathway and NF-κB pathway. Thus, triptolide may be used as a potential drug to treat SS.

Colonization and immunoregulation of Lactobacillus plantarum BF_15, a novel probiotic strain from the feces of breast-fed infants

Immunosuppression is a manifestation imbalance in the immune system, often during unhealthy states. In recent years, lactic acid bacteria (LAB) have been found to be important components of the body's innate immune system, and indispensable to maintaining normal immune function. Lactobacillus plantarum BF_15, a novel strain isolated from the feces of breast-fed infants, which has shown potential as an immunomodulator in vitro. In the present study, with the Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) based on RNA-polymerase beta subunit encoding gene (rpoB) to analyze the colonization of L. plantarum BF_15 in the intestine of mice. In addition, Lactobacillus rhamnosus GG (LGG) as a positive control strain, by measuring immune-related indexes and the diversity of intestinal microbiota, the effects of BF_15 on immunoregulation and intestinal microbiota dysbiosis were investigated to elucidate whether the attenuation of immunosuppression is related to the modulation of intestinal microbiota. Results did indeed support this notion that BF_15 did colonize murine intestines well, in which it could still be detected in mice feces 14 days after stopping the probiotic administration. Moreover, BF_15 found to protect mice against reduction in the levels of several immune-related indicators, including the thymus and spleen indexes, splenic lymphocyte proliferation, toe swelling degree, serum hemolysin-antibody level, and macrophage phagocytosis index, triggered by high-dose (200 mg kg-1) intraperitoneal administration of cyclophosphamide (CTX). In addition, the strain was also found to effectively balance intestinal microbiota dysbiosis in the mice. Collectively, these results indicated that L. plantarum BF_15 can not only successfully colonize murine intestines, but also can effectively alleviate CTX-induced immunosuppression, once established, by rebalancing the intestinal microbiota. This, therefore, provides strong evidence for the view that BF_15 has the potential to become a highly effective immunomodulating probiotic in human microbiota as well.

Immunomodulatory activity of puerarin in RAW264.7 macrophages and cyclophosphamide-induced immunosuppression mice

CONTEXT

Puerarin, a natural isoflavone extracted from Radix puerariae, is famous for treating various cardiovascular and cerebrovascular diseases. However, little is known about its direct immunomodulatory activity.

OBJECTIVE

This study was designed to investigate the in vitro and in vivo immunomodulatory effects of Radix puerariae by using the murine monocyte-macrophage cell line RAW264.7 and immunosuppressed cyclophosphamide-induced mice.

METHODS

MTT and neutral red phagocytosis assays were conducted to evaluate the in vitro immunomodulatory activities of puerarin on cell viability and phagocytosis by measuring the proliferation, phagocytic, nitric oxide (NO) ability, and TNF-α production ability of stimulated and lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Immunosuppressed cyclophosphamide-induced mice were used to evaluate the in vivo immunomodulatory activities of puerarin by measuring IL-4 and IFN-γ, the serum half hemolysis value, spleen and thymus index, and proliferation assay for splenic lymphocytes.

RESULTS AND DISCUSSION

Results showed that puerarin improves immunomodulatory activity by increasing cell proliferation, cell phagocytosis, and NO secretion in RAW264.7 macrophages and reduces the abnormal immunologic activity by decreasing cell phagocytosis and NO secretion in LPS-stimulated RAW264.7 macrophages. In addition, puerarin enhanced the immunologic activity of cyclophosphamide-induced immunosuppression mice by increasing the secretion of NO, IFN-γ, and IL-4, the serum half hemolysis value (HC₅₀), the spleen and thymus index, and proliferation for splenic lymphocytes.

CONCLUSION

Puerarin exhibited an upregulated immunomodulatory effect on RAW264.7 macrophages and immunosuppression mice. In addition, puerarin had a downregulated immunomodulatory effect on RAW264.7 macrophages. The results suggest that puerarin could be a promising immunomodulator to assist in the treatment of tumors.

Short-term exposure of decabromodiphenyl ether in female adult Balb/c mice: Immune toxicity and self-recovery

As a typical persistent organic pollutant, decabromodiphenyl ether (BDE-209) is associated with various health risks, especially on immune system, which is sensitive to environmental pollutants. In addition, there is a problem of multi-index estimation and lack of comprehensive evaluation in immune toxicity study. In this study, the immunotoxicity of BDE-209 was systematically estimated from the aspects of immunopathology, humoral immunity, cellular immunity and non-specific immunity, etc., and integrated biomarker responses (IBR) combined with principal component analysis was applied to comprehensively evaluate the immunotoxicity of BDE-209 and its self-recovery after discontinuation. Results showed that BDE-209 exposure could cause immunotoxicity. This response seems to depend on (1) atrophying immune organs (thymus and spleen), hepatomegaly accompanied by increasing aspartate aminotransferase and oxidative stress;(2) changing humoral (immunoglobulins) and cellular (lymphocyte proliferation and cytokine secretion) immunity indices; (3) altering related expressions of genes, and further leading to imbalance of Th1/Th2 (Th, helper T cell). Integrated biomarker responses (IBR) companied with principal component analysis selected five biomarkers (mRNA expression of GATA-3, malondialdehyde level in thymus, count of white blood cell, serum IgG and lipopolysaccharide-induced splenic lymphocyte proliferation) to clarify the immunotoxicity induced by BDE-209. Furthermore, IBR combined with factorial analysis revealed that the effect of BDE-209 could be dose-dependently reduced after withdrawal of BDE-209. Overall results suggested that BDE-209 has immunotoxicity on adult Balb/c mice, whereas this immunotoxicity could be reduced by the self-regulation of organisms to some extent.