Ameliorative effect of Trametes orientalis polysaccharide against immunosuppression and oxidative stress in cyclophosphamide-treated mice

Lacticaseibacillus casei K11 exerts immunomodulatory effects by enhancing natural killer cell cytotoxicity via the extracellular regulated-protein kinase pathway

PURPOSE

Probiotics can serve as immunomodulators that regulate the activation of immune cells. This study aimed to screen potential probiotic strains that can enhance NK cell toxicity to improve host immunity.

METHODS

In this investigation, we examined three potential probiotic strains, namely Lactiplantibacillus plantarum YZX21 (YZX21), Bifidobacterium bifidum FL-276.1 (FL-276.1) and Lacticaseibacillus casei K11 (K11), to assess their capacity in modulating NK cytotoxicity both in vitro and in vivo, while elucidating the underlying mechanisms involved.

RESULTS

The findings demonstrated that K11 exhibited superior efficacy in enhancing NK cytotoxicity. Subsequent analysis revealed that K11 significantly augmented the secretion of perforin and granzyme B by NK cells through activation of receptors NKp30 and NKp46 via the extracellular signal-regulated kinase (ERK) pathway. Furthermore, heat-inactivated K11 also enhanced NK cell activity to an extent comparable to live bacteria, with lipoteichoic acid from K11 identified as a crucial factor mediating the activation of NK cell cytotoxicity.

CONCLUSION

Our study suggests that K11 may have potential applications as probiotics or postbiotics for regulating NK cell cytotoxicity to enhance immunity.

Mulberry leaf polysaccharide improves cyclophosphamide-induced growth inhibition and intestinal damage in chicks by modulating intestinal flora, enhancing immune regulation and antioxidant capacity

Polysaccharides are generally considered to have immune enhancing functions, and mulberry leaf polysaccharide is the main active substance in mulberry leaves, while there are few studies on whether mulberry leaf polysaccharide (MLP) has an effect on immunosuppression and intestinal damage caused by cyclophosphamide (CTX), we investigated whether MLP has an ameliorative effect on intestinal damage caused by CTX. A total of 210 1-day-old Mahuang cocks were selected for this experiment. Were equally divided into six groups and used to evaluate the immune effect of MLP. Our results showed that MLP significantly enhanced the growth performance of chicks and significantly elevated the secretion of cytokines (IL-1β, IL-10, IL-6, TNF-α, and IFN-γ), immunoglobulins and antioxidant enzymes in the serum of immunosuppressed chicks. It attenuated jejunal damage and elevated the expression of jejunal tight junction proteins Claudin1, Zo-1 and MUC2, which protected intestinal health. MLP activated TLR4-MyD88-NF-κB pathway and enhanced the expression of TLR4, MyD88 and NF-κB, which served to protect the intestine. 16S rDNA gene high-throughput sequencing showed that MLP increased species richness, restored CTX-induced gut microbiome imbalance, and enhanced the abundance of probiotic bacteria in the gut. MLP improves cyclophosphamide-induced growth inhibition and intestinal damage in chicks by modulating intestinal flora and enhancing immune regulation and antioxidant capacity. In conclusion, this study provides a scientific basis for MLP as an immune enhancer to regulate chick intestinal flora and protect chick intestinal mucosal damage.

A review on extraction, composition, structure, and biological activities of polysaccharides from different parts of Nelumbo nucifera

Nelumbo nucifera (lotus plant) is an important member of the Nelumbonaceae family. This review summarizes the studies conducted on it since the past 15 years to provide an understanding on future areas of focus. Different parts of this plant, that is, leaves, roots, and seeds, have been used as food and for the treatment of various diseases. Polysaccharides have been extracted from different parts using different methods. The manuscript reviews the methods of extraction of polysaccharides used for leaves, roots, and seeds, along with their yield. Some methods can provide better yield while some provide better biological activity with low yield. The composition and structure of extracted polysaccharides have been determined in some studies. Although monosaccharide composition has been determined in various studies, too little information about the structure of polysaccharides from N. nucifera is available in the current literature. Different useful biological activities have been explored using in vivo and in vitro methods, which include antioxidant, antidiabetic, antitumor, anti-osteoporotic, immunomodulatory, and prebiotic activities. Antitumor activity from polysaccharides of lotus leaves is yet to be explored, besides lotus root has been underexplored as compared to other parts (leaves and seeds) according to our literature survey. Studies dedicated to the successful use of combination of extraction methods can be conducted in future. The plant provides a therapeutic as well as nutraceutical potential; however, antimicrobial activity and synergistic relationships of polysaccharides from different parts of the plant need further exploration.

Polysaccharides From the Aerial Parts of Tetrastigma Hemsleyanum Diels et Gilg Induce Bidirectional Immunity and Ameliorate LPS-Induced Acute Respiratory Distress Syndrome in Mice

Tetrastigma hemsleyanum Diels et Gilg (Sanyeqing, SYQ) has traditionally been used to treat inflammation, high fever and improve immune function of patients. Polysaccharides have been proved to be one of the important components of SYQ. Previous studies have confirmed the antipyretic and antitumor effects of polysaccharides from SYQ (SYQP), and clarified that SYQP could enhance immunity through TLR4 signalling pathway. However, there were more possibilities for the mechanism by which SYQP exerted immunomodulatory effects and the role of SYQP in acute respiratory distress syndrome (ARDS) is elusive. The purpose of this study was further to explain the bidirectional modulation of immunity mechanism of SYQP in vitro and its effect in LPS-induced ARDS in vivo. Experimental results showed that SYQP significantly stimulated gene expressions of TLR1, TLR2 and TLR6 and secretion of cytokines in RAW264.7 cells. Individual or combined application of TLR2 antagonist C29 and TLR4 antagonist TAK-242 could reduce SYQP-mediated stimulation of cytokine secretion in RAW264.7 cells and mouse peritoneal macrophages (MPMs) to varying degrees. On the other hand, SYQP markedly inhibited the expression levels of inflammatory cytokines, NO, iNOS and COX-2 in LPS-treatment RAW264.7 cells. Moreover, in vivo results indicated that SYQP significantly reduced LPS-induced damage in ARDS mice through alleviating LPS-induced pulmonary morphological damage, inhibiting myeloperoxidase (MPO) expression levels, ameliorating the inflammatory cells in bronchoalveolar lavage fluid (BALF) and improving hematological status. Meanwhile, SYQP evidently reduced IL-6, TNF-α and IFN-γ secretion, the overexpression levels of TLR2 and TLR4, as well as the phosphorylation of NF-κB p65. In addition, SYQP reduced the phosphorylation of JAK2 and STAT1 and the overexpression of NLRP3, caspase-1, caspase-3 and caspase-8 in lung tissues of ARDS mice. In summary, our study confirmed that SYQP induced bidirectional immunity and ameliorated LPS-induced acute respiratory distress syndrome in mice through TLR2/TLR4-NF-κB, NLRP3/caspase and JAK/STAT signaling pathways, which provided a theoretical basis for further use of SYQP.

Effects of Koumiss on Intestinal Immune Modulation in Immunosuppressed Rats

Koumiss is a traditional fermented dairy product with health and medicinal benefits. It is very popular in the Inner Mongolia Autonomous Region of China. The results of relevant studies have shown that koumiss can regulate the gastrointestinal environment, improve the absorption of nutrients, improve the body's intolerance to lactose, enhance the body's immunity, prevent scurvy and atherosclerosis, and aid in the treatment of tuberculosis. However, there are no systematic reports on the effects of koumiss on immunity. In this study, we aimed to decipher the effects of koumiss on intestinal immune modulation. We used liquid chromatography-tandem mass spectrometry (LC-MS) analysis to determine the composition of Koumiss. Using Compound Discoverer software, we compared the mass spectrometry data with the compound information in the online databases ChemSpider and mzCloud to intelligently identify the main chemical components of koumiss. Additionally, we used Mass Frontier small molecule fragmentation library^TM to determine the structure of fragment ions. A total of 21 components were identified, which clarified the chemical basis of koumiss. These 21 compounds were then used to perform molecular docking with immune-related targets, such as TNF, IL2, IL10, etc. The results indicated good docking activity between most of the compounds and the targets. Then, an immunosuppressive rat model was used to determine the therapeutic effect of koumiss. The results of this study showed that koumiss could, to a certain extent, correct the atrophy of the thymus and spleen in immunosuppressed model rats. The number of leukocytes, lymphocytes, and the CD4⁺/CD8⁺ ratio of peripheral blood lymphocytes was also increased. In addition, it could effectively improve the structure of the small intestinal mucosa, which shows that koumiss has a positive effect on the intestinal immune function of immunosuppressed rats. These findings provide an experimental basis for the development and utilization of koumiss as a therapeutic product.

Sulfated modification enhances the immunomodulatory effect of Cyclocarya paliurus polysaccharide on cyclophosphamide-induced immunosuppressed mice through MyD88-dependent MAPK/NF-κB and PI3K-Akt signaling pathways

The present study investigated the effect of sulfation on the immunomodulatory effect of Cyclocarya paliurus polysaccharide (CP) through a Cyclophosphamide (CTX)-induced immunosuppression mice model. The results showed that sulfated Cyclocarya paliurus polysaccharide (SCP3) had stronger immunomodulatory ability than CP. Administration of SCP3 alleviated immune organ atrophy and restored hematopoiesis in immunosuppressed mice, enhanced splenocyte proliferation, and promoted cytokines and nitric oxide (NO) production in splenocyte supernatants, as well as the number of CD3+, CD4+ and CD8+ T lymphocytes. Meantime, SCP3 significantly improved oxidative stress via increasing the activities of antioxidant enzymes and decreasing the levels of malondialdehyde (MDA) in liver. In addition, SCP3 significantly upregulated the phosphorylation expression of JNK, Erk 1/2, p38 of MAPKs signaling pathway at a dose of 50 mg/kg and accordingly showed increased phosphorylation of Akt, NF-κB (p65), IκB-α, and promoted the degradation of IkB-α. Furthermore, SCP3 significantly increased the expression of the upstream signaling molecule MyD88. All results demonstrated that sulfation can be an effective way to enhance the immunomodulatory effect of polysaccharides. SCP3 has high potential to be a functional food supplement candidate for alleviating chemotherapy drug-induced immunosuppression.

Protective effect of myricetin, apigenin, and hesperidin pretreatments on cyclophosphamide-induced immunosuppression

Aim: Major side effects of cyclophosphamide administration are immunosuppression and myelosuppression. The immunomodulatory effects of plant bioactive compounds on chemotherapy drug-induced immunosuppression may have significant effects in cancer treatment. For this reason, we investigated the immunomodulatory effect of myricetin, apigenin, and hesperidin in cyclophosphamide-induced immunosuppression in rats.Methods: In our study, a total of 64 rats were used, and divided into eight equal groups. These groups were: control, cyclophosphamide, cyclophosphamide + myricetin (100 mg/kg), cyclophosphamide + myricetin (200 mg/kg), cyclophosphamide + apigenin (100 mg/kg), cyclophosphamide + apigenin (200 mg/kg), cyclophosphamide + hesperidin (100 mg/kg), and cyclophosphamide + hesperidin (200 mg/kg). Myricetin, apigenin, and hesperidin pretreatments were performed for 14 d, while cyclophosphamide application (200 mg/kg) was performed only on the 4th day of the study. Levels of humoral antibody production, quantitative hemolysis, macrophage phagocytosis, splenic lymphocyte proliferation, and natural killer cell cytotoxicity were determined. In addition, we measured pro-inflammatory cytokines, and followed lipid peroxidation and antioxidant markers and examined the histology of bone marrow, liver and spleen in all groups.Results: During cyclophosphamide treatment, all three phytochemicals increased the levels of humoral antibody production, quantitative hemolysis, macrophage phagocytosis, splenic lymphocyte proliferation, antioxidant markers, and natural killer cell cytotoxicity. Moreover, the agents decreased the levels of pro-inflammatory cytokines and mediators, reduced lipid peroxidation markers, and reduced tissue damage in liver, spleen, and bone marrow.Conclusion: Our study demonstrated that myricetin, apigenin, and hesperidin can reduce the immunosuppressive effect of cyclophosphamide by enhancing both innate and adaptive immune responses, and these compounds may be useful immunomodulatory agents during cancer chemotherapy.

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.

Modulation of gut homeostasis by exopolysaccharides from Aspergillus cristatus (MK346334), a strain of fungus isolated from Fuzhuan brick tea, contributes to immunomodulatory activity in cyclophosphamide-treated mice

In this study, the crude exopolysaccharides (CEPSs) from fungus Aspergillus cristatus (MK346334, NCBI) isolated from Fuzhuan brick tea and its main purified fraction (EPSs-2) were investigated. Using the RAW264.7 cell model, EPSs-2 exhibited an excellent immunomodulatory effect in vitro. Then, the regulating effects of EPSs on immune function and gut microbiota were evaluated using a cyclophosphamide (Cy)-induced mice model. It was found that both CEPSs and EPSs-2 improved the body weight loss, immune organ indexes as well as the levels of TNF-α, IL-1β, IFN-γ and IgA, exhibiting potent immunoregulatory activity. Moreover, CEPSs and EPSs-2 not only attenuated the intestinal tissue damage, but also promoted the production of short-chain fatty acids and modulated the microbial composition by increasing the growth of Muribaculaceae, Prevotellaceae_UCG-001, Bacteroides, Parabacteroides and Tidjanibacter, while decreasing the relative abundances of Helicobacter, Bilophila, Mucispirillum, Lachnospiraceae, Ruminococcaceae and Clostridiales. These results indicated that the EPSs, especially EPSs-2, exhibited immunomodulatory activity associated with the modulation of gut microbiota to maintain gut homeostasis, which provided evidence for the development of novel potential prebiotics and immunomodulators.

Antioxidative stress of oral administration of tea extract granule in chickens

The present study was to evaluate antioxidative effect of tea extract granule (TEG) on oxidative stress induced by cyclophosphamide (Cy) in chickens. In experiment 1, chickens were randomly divided into 5 groups with 10 birds in each. Groups 3 to 5 were orally administered TEG in drinking water for 7 D at doses of 20, 40, and 80 mg/kg body weight, respectively. After that, groups 2 to 5 received intramuscular injection of Cy (100 mg/kg BW) for 3 D. Group 1 was not treated as a control. In experiment 2, chickens were grouped in the same way as in experiment 1. Groups 2 to 5 received intramuscular injection of Cy (100 mg/kg BW) for 3 D. After that, groups 3 to 5 were orally administered TEG in drinking water for 7 D at doses of 20, 40, and 80 mg/kg BW, respectively. Results showed that Cy injection induced significantly decreased body weight and oxidative stress. Oral administration of TEG before or after Cy injection increased body weight, the thymus, bursa, and spleen indices, total antioxidant capacity, and the levels of glutathione; elevated the activity of superoxide dismutase, catalase, and glutathione peroxidase; as well as decreased the protein carbonyl content, lipid peroxide, and malondialdehyde. In addition, TEG administration reduced intracellular reactive oxygen species. Therefore, TEG could be a promising agent against oxidative stress in the poultry industry.

Effect of enzyme-assisted extraction on the physicochemical properties and bioactive potential of lotus leaf polysaccharides

Lotus leaf polysaccharides were extracted by enzyme-assisted extraction using α-amylase (LLEP-A), cellulose (LLEP-C), pectinase (LLEP-P) or protease (LLEP-PR). Their physicochemical properties and immunostimulatory activities were compared with those of hot-water extracted polysaccharides (LLWP). HPAEC-PDA and HPSEC-RI profiles indicated that variations in their molecular weight patterns and chemical compositions. Moreover, their effects on proliferation, phagocytic activity, and cytokine production in macrophages could be ordered as LLEP-P > LLEP-C > LLEP-A > LLWP > LLEP-PR, suggesting that LLEP-P by pectinase-assisted extraction was the most potent enhancer of macrophage activation. LLEP-P was further purified by gel filtration, and the main fraction (LLEP-P-І) was obtained to elucidate the structural and functional properties. LLEP-P-І (14.63 × 10³ g/mol) mainly consisted of rhamnose, arabinose, galactose, and galacturonic acid at molar percentages of 15.5:15.8:20.1:32.8. FT-IR spectra indicated the predominant acidic and esterified form, suggesting the pectic-like structure. Above all, LLEP-P-І exerted greater stimulation effects on NO and cytokines production and the phagocytic activity in macrophages. Transcriptome analysis also demonstrated that LLEP-P and LLEP-P-І could upregulate macrophage immune response genes, including cytokines, chemokines, and interferon via TLR and JAK-STAT signaling. Thus, these results suggest that pectinase application is most suitable to obtain immunostimulatory polysaccharides from lotus leaves.

Purification, structural elucidation and in vivo immunity-enhancing activity of polysaccharides from quinoa (Chenopodium quinoa Willd.) seeds

Quinoa crude polysaccharides (QPS) were extracted from Chenopodium quinoa Willd. The soluble non-starch polysaccharide fraction (QPS1) was subsequently purified by DEAE-52 cellulose and Sephadex G-50 gel chromatography, using QPS as raw materials. Its chemical structure was identified using FT-IR, NMR, AFM, SEM and Congo red staining. High performance gel permeation chromatography (HPGPC) was used to determine molecular weight, and composition by HPLC. QPS1, with a molecular weight of 34.0 kDa, was mainly composed of mannose, rhamnose, galacturonic acid, glucose, galactose, xylose and arabinose at a molar ratio of 2.63:2.40:1.64:6.28:1.95:2.48:5.01. In addition, we evaluated the ameliorative effects of QPS1 on the improvement of anti-cyclophosphamide (CTX)-induced immunosuppression in ICR mice. The result exhibited significantly immune-enhancing activity: QPS1 successfully improved the content of IFN-γ, IL-6, IFN-ɑ, IgM and lysozyme (LYSO) in serum for three weeks, enhanced the phagocytic function of mononuclear macrophages and ameliorated delayed allergy in mice.

Water-soluble polysaccharides from Grifola Frondosa fruiting bodies protect against immunosuppression in cyclophosphamide-induced mice via JAK2/STAT3/SOCS signal transduction pathways

Grifola Frondosa, the king of mushrooms, is one of the most valued traditional medicines and has been used as a health food for a long time in China, Japan, and other Asian countries. The present study was designed to evaluate the immune-modulating effects of water-soluble polysaccharides from the Grifola Frondosa fruiting body (GFP) by using mouse peritoneal macrophage and cytoxan (CTX) induced immunosuppression models. Compared with CTX-induced immunosuppressive mice, the spleen and thymus indexes in mice with GFP orally administrated were significantly increased, body weight loss was alleviated, and the natural killer (NK) cytotoxicity and the proliferative activities of lymphocytes were elevated. Furthermore, levels of interleukin-2 (IL-2), interferon-6 (IL-6) and tumor necrosis factor-α (TNF-α) were notably reduced by CTX, while GFP abolished these effects. GFP also effectively increased total antioxidant capacity and superoxidase dismutase, catalase and glutathione peroxidase activities, and inhibited an increase in the malondialdehyde level. Histopathological analysis of spleens revealed the protective effect of GFP against CTX-induced immunosuppression. Western blotting results showed that GFP possessed immunomodulatory activity by up-regulating transcription factors (p-JAK2/JAK2, p-STAT3/STAT3 and SOCS3) in JAK2/STAT3/SOCS signaling pathways. This study suggested that GFP may provide an alternative strategy for lessening chemotherapy-induced immunosuppression.

Ovotransferrin ameliorates the dysbiosis of immunomodulatory function and intestinal microbiota induced by cyclophosphamide

In this study, the regulative effects of ovotransferrin (OVT) on immunomodulatory function and intestinal microbial dysbiosis in a mouse model injected with cyclophosphamide (CP) were investigated. The immunomodulatory effect of OVT was determined by enzyme-linked immune sorbent assay (ELISA). Gut microbial composition was determined by high-throughput sequencing of the V3-V4 region of the 16S rDNA gene. The changes in the relative abundance of the dominant microbiota were analyzed at different taxonomic levels. The results showed that OVT alleviated the immune dysfunction caused by CP. OVT improved the spleen and thymus indices and enhanced the secretion of tumor necrosis factor alpha (TNF-α), interleukin-10 (IL-10), and immunoglobulin A (IgA). In addition, OVT increased the indexes of Shannon and Simpson, suggesting the enhancement of the diversity and richness of intestinal microflora. The relative abundance of Lachnospiraceae_NK4A136_group was also increased. However, the relative abundance of Helicobacter and Desulfovibrio was significantly decreased. These results indicated that OVT, a food-derived functional component, has effects on immune regulation in the organism and ameliorates the gut microbiota disorders induced by CP, which provides a potential therapeutic utilization of avian eggs by targeting the gut microbiome.

Protective effects of Panax notoginseng saponins on PME-Induced nephrotoxicity in mice

Polymyxin E (PME) plays an important role in fighting against Gram-negative bacterial infections; however, it causes nephrotoxicity, which limits its clinical use. The aim of this study was to investigate the protective effects of a plant extract Panax notoginseng saponins (PNS) on PME-induced nephrotoxicity in mice. In vivo studies showed that PNS significantly reduced blood urea nitrogen (BUN), serum creatinine (CRE) and number of apoptotic cells in kidney, as well as renal histopathological damage which increased in the presence of PME, and suppressed PME-induced oxidative stress in kidney, as shown by the up-regulation of superoxide dismutase (SOD) and the down-regulation of malondialdehyde (MDA) levels. Furthermore, PNS inhibited the expression of Bax, while increased the expression of Bcl-2 compared to the PME-treated group. In vitro studies showed that PNS decreased intracellular reactive oxygen species (ROS) and MDA levels, increased glutathione (GSH) levels, and enhanced the activity of SOD and glutathione peroxidase (GSH-Px) in murine renal tubular epithelial cells (TCMK-1 cells). In addition, PNS enhanced cell viability and the expression of Bcl-2, restored the mitochondrial membrane potential, inhibited the expression of Bax, inhibited the activity of caspase-3 and caspase-9, and reduce apoptotic rate in PME-treated TCMK-1 cells. PNS could reduce PME-induced nephrotoxicity. The protective effects could result from inhibition of oxidative stress, and prevention of cell apoptosis via the mitochondrial pathway. These findings highlight the potential of PNS as a safe adjunct for ameliorating the nephrotoxicity.

Glycosaminoglycan from Apostichopus japonicus induces immunomodulatory activity in cyclophosphamide-treated mice and in macrophages

This study was designed to systematically elucidate the immunomodulation effect of glycosaminoglycan from Apostichopus japonicus (AHG) in cyclophosphamide (CY)-induced immunosuppression model and potential mechanism responsible for the activation of macrophages. The results showed that the treatment with AHG could increase natural killer (NK) cell cytotoxicity, carbon clearance and marker enzymes activities in CY-induced immunosuppression mice, indicating that the innate immunity experienced recovery to some extent. Moreover, CY-induced reductions in thymus and spleen indices, serum levels of cytokines, immunoglobulins and hemolysin, as well as the ratio of spleen lymphocyte subsets were recovered by AHG, suggesting that AHG could improve the adaptive immunity through cellular immunity and humoral immunity. Delightedly, it was found that AHG at 10 mg/kg body weight could restore the CY-induced immunosuppression in mice to normal level on both innate and adaptive immunity. Furthermore, AHG also promoted both the expression of NO, TNF-α, IL-6, IL-1β, IL-18 and MCP-1 protein and related mRNA in macrophages. It was revealed that AHG activated macrophages through the phosphorylation of mitogen-activated protein kinase (MAPK) and nuclear factor-B (NF-κB). In conclusion, AHG exerts remarkable immunomodulatory activities in both innate and adaptive immune system. These findings should have great value for further study on the immunopotentiating mechanisms of this biomacromolecule.

Immune-enhancing effects of anionic macromolecules extracted from Codium fragile on cyclophosphamide-treated mice

Immune-regulation and homeostasis are critical in cancer therapy and immunomodulatory biomaterials have been used to decrease side effects of immunosuppressant drugs. Anionic macromolecules (CFAMs) were isolated from the seaweed Codium fragile, and its immune-enhancing biological activities were examined in CY-induced immunosuppressed mice. CFAMs improved the splenic lymphocyte proliferation, NK cell activity, and spleen index. The expression of immune-associated genes was highly upregulated in splenic lymphocytes, and gene expression was differently regulated according to mitogens such as T-cell (Con A) and B-cell (LPS) mitogens. Additionally, CFAMs boosted the proliferation, NO production, and phagocytosis of peritoneal macrophages. CFAMs also considerably stimulated immune-associated gene expression in peritoneal macrophages. Moreover, our results showed CFAMs mediated its immune-enhancing effects via the MAPK pathway. These suggested CFAMs can be used as a potent immunomodulatory material under immune-suppressive condition. Furthermore, CFAMs may also be used as a bio-functional and pharmaceutical material for improving human health and immunity.

Scutellarin Exerts Hypoglycemic and Renal Protective Effects in db/db Mice via the Nrf2/HO-1 Signaling Pathway

This study investigated the hypoglycemic and renal protective effects of scutellarin (SCU) in db/db mice and elucidated the underlying mechanisms. The oral administration of metformin hydrochloride (Met) at 120 mg/kg and SCU at 25, 50, and 100 mg/kg over an eight-week period had hypoglycemic effects, demonstrated by decreases in body weight, blood glucose, food and water intake, and glycated hemoglobin activity and by augmented insulin levels and pyruvate kinase activity in the serum of db/db mice. SCU alleviated dyslipidemia by decreasing the levels of triglycerides and total cholesterol and enhancing the levels of high-density lipoprotein cholesterol in the serum of db/db mice. SCU reversed the overexpression of mRNA of renal damage markers (receptor for advanced glycation end products, neutrophil gelatinase-associated lipocalin, and kidney injury molecule 1), macrophage marker CD11b, and T cell marker CD3 in kidney of db/db mice. Pathological examination confirmed that SCU improved the organ structures of hyperglycemia-damaged livers, kidneys, and pancreas islets. Antibody array assay and enzyme-linked immunosorbent assay were combined to screen and analyze the regulatory effects of SCU on inflammatory factors and oxidative enzymes. SCU exerted anti-inflammatory effects by inhibiting the levels of proinflammatory cytokines (glycogen synthase kinase, intercellular adhesion molecule 2, and interleukin 1β and 2) and promoting anti-inflammatory cytokines (interleukin 4). SCU decreased the reactive oxygen species and malondialdehyde concentrations and increased the activity levels of antioxidative enzymes (superoxide dismutase, glutathione peroxidase, and catalase) in serum and kidneys. Furthermore, SCU upregulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), which in turn improved heme oxygenase 1 (HO-1), superoxide dismutase 1 and 2, and catalase expression levels in kidneys. The study showed that SCU has at least partial hypoglycemic and renal protective effects in db/db mice, and the mechanism is the modulation of the Nrf2/HO-1 signaling pathway.

Optimization of Ultrasonic-Microwave Assisted Extraction and Hepatoprotective Activities of Polysaccharides from Trametes orientalis

Ultrasonic-microwave assisted extraction (UMAE) of Trametes orientalis polysaccharides was optimized by response surface methodology. Hepatoprotective effects of a purified T. orientalis polysaccharide (TOP-2) were evaluated by alcohol-induced liver injury model mice. The optimal UMAE parameters were indicated as below: ratio of water to raw material 28 mL/g, microwave power 114 W, extraction time 11 min. The polysaccharides yield was 7.52 ± 0.12%, which was well consistent with the predicted value of 7.54%. Pre-treatment with TOP-2 effectively increased the liver index and spleen index in alcohol-treated mice. The elevated serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels of mice after alcohol exposure were inhibited by TOP-2 administration. The liver tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) levels have decreased significantly as a result of alcohol exposure, while pre-treatment with TOP-2 could mitigate these consequences. Furthermore, pre-treatment with TOP-2 could efficiently boost the superoxidase dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities, and observably constrain the malondialdehyde (MDA) level. The findings suggest that TOP-2 might be useful for alleviating the alcohol-induced hepatotoxicity via its antioxidant and anti-inflammatory potential.

The impacts of natural polysaccharides on intestinal microbiota and immune responses – a review

This paper presents a comprehensive review of the impacts of natural polysaccharides on gut microbiota and immune responses as well as their interactions.

Trametes orientalis polysaccharide alleviates PM2.5-induced lung injury in mice through its antioxidant and anti-inflammatory activities

Trametes orientalis polysaccharide (TOP-2) could alleviate PM_2.5-induced lung injury in mice via its antioxidant and anti-inflammatory activities.

Immune-enhancing effects of polysaccharides from purple sweet potato

Immune-enhancing effects of three kinds of purple sweet potato polysaccharides (PSPPs) including water-soluble polysaccharide (WSP), dilute alkali-soluble polysaccharide (DASP) and concentrated alkali-soluble polysaccharide (CASP) were evaluated. Scanning electron microscope analysis showed that all PSPPs could stimulate the formation of microvilli-like structures in cellular surfaces, which was possibly related to activation of macrophages. Neutral red uptake assay showed that PSPPs could increase the phagocytic activity of cells. High dose (400 μg/mL) of PSPPs could notably augment the level of nitric oxide (NO). ELISA analysis revealed that 200 and 400 μg/mL of PSPPs distinctly elevated the production of IL-1β. Cells received 200 and 400 μg/mL of WSP as well as 400 μg/mL of DASP exhibited higher level of IL-6. Results of animal experiments showed that WSP treatment (400 mg/kg) could promote the secretions of IgA, IgG, IgM and sIgA in both normal and immunosuppressed mice. Moreover, CASP treatment (400 mg/kg) elevated the production of IgM in the serum of normal and immunosuppressive mice, while DASP (400 mg/kg) only improved the secretion of IgM in normal mice. In summary, all three polysaccharides can stimulate immune responses of macrophages and positively regulate adaptive immunity by enhancing the production of immunoglobulins in mice.

Immunomodulatory activity of a novel polysaccharide from Lonicera japonica in immunosuppressed mice induced by cyclophosphamide

Lonicera japonica is a typical Chinese herbal medicine. We previously reported a method to isolate polysaccharides from Lonicera japonica (LJP). In this study, we first performed a qualitative analysis of LJP using the Fourier Transform Infrared Spectrometer (FT-IR) and explored the monosaccharide composition of LJP using the pre-column derivatization high performance liquid chromatography (HPLC) method. We then investigated the immunomodulatory function of LJP in cyclophosphamide (CTX)-induced immunosuppressed mouse models. The results showed that LJP had the characteristic absorption of typical polysaccharides consisting of 6 types of monosaccharides. In addition, LJP can increase significantly the organ index, splenic lymphocyte proliferation, macrophage phagocytosis, and natural killer (NK) cell activity in CTX-treated mice. LJP could also restore the levels of serum cytokines interleukin (IL-2), tumor necrosis factor (TNF-α) and Interferon-γ (IFN-γ) in the CTX-treated mice. Finally, the results on measuring the T-lymphocytes subsets of spleen also confirmed LJP-induced immunomodulatory activity in immunosuppressed mice from another perspective. Therefore, LJP could be used as a potential immunomodulatory agent.

The Polysaccharides from Codonopsis pilosula Modulates the Immunity and Intestinal Microbiota of Cyclophosphamide-Treated Immunosuppressed Mice

Based on previous studies about microflora regulation and immunity enhancement activities of polysaccharides from Codonopsis pilosula Nannf. var. modesta (Nannf.) L. T. Shen (CPP), there is little study on intestinal mucosal immunity, which is a possible medium for contacting microflora and immunity. In the present study, the BALB/c mice were divided into five groups (eight mice in each group), including a normal group (Con), a model control group (Model), and model groups that were administered CPP (50, 100, 200 mg/kg/d) orally each day for seven days after intraperitoneal injection of 60 mg/kg BW/d cyclophosphamide (CP) for three days. CPP recovered the spleen index and restored the levels of IFN-γ, IL-2, IL-10, as well as serum IgG. In addition, it elevated ileum secretory immunoglobulin A (sIgA), the number of Lactobacillus and acetic acid content in cecum. These results indicated that CPP plays an important role in the protection against immunosuppression, especially mucosa immune damage, and the inhibition of pathogenic bacteria colonization, which could be considered a potential natural source of immunoregulator.

Prevention of Cyclophosphamide-Induced Immunosuppression in Mice with the Antimicrobial Peptide Sublancin

Sublancin is a glycosylated antimicrobial peptide produced by Bacillus subtilis 168 with combined antibacterial and immunomodulatory activities. The purpose of this study was to evaluate the protective effects of sublancin on immunosuppression in cyclophosphamide-treated mice. In normal mice, the phagocytic activity of mouse peritoneal macrophages was significantly enhanced by oral administration of sublancin (1.0 mg/kg body weight) to BALB/c mice for 7 days (P < 0.01). In addition, the mRNA expression of IL-1β, IL-6, and TNF-α in peritoneal macrophages from sublancin- (1.0 mg/kg body weight) administered mice was significantly increased (P < 0.05). In cyclophosphamide-treated mice, oral sublancin administration accelerated the recovery of peripheral white blood cells, red blood cells, hemoglobins, and platelets and enhanced the macrophage phagocytic activity. Furthermore, sublancin restored the mRNA levels of IL-2, IL-4, and IL-6 in the spleen. Finally, the intestinal absorption of sublancin was poor as detected in the Caco-2 transwell system. Taken together, these findings suggest that sublancin plays a crucial role in the protection against immunosuppression in cyclophosphamide-treated mice and could be a potential candidate for use in immune therapy regimens.

Effects of polysaccharides from purple sweet potatoes on immune response and gut microbiota composition in normal and cyclophosphamide treated mice

Three polysaccharides were extracted from purple sweet potatoes and then administered to normal and cyclophosphamide treated mice by gavage.

Immunoenhancement of Edible Fungal Polysaccharides (Lentinan, Tremellan, and Pachymaran) on Cyclophosphamide-Induced Immunosuppression in Mouse Model

Fungal polysaccharides display a variety of important biological activities, including anti-inflammatory, antitumor, and immune-stimulating activities. The aim of present study was to investigate the immunomodulatory effect of fungal polysaccharides on cyclophosphamide-induced immunosuppression in mice. Mice were pretreated orally with lentinan, tremellan, pachymaran, or a mixture of the three, respectively. The results showed that pretreatments with polysaccharides significantly increased the thymus index in cyclophosphamide-induced immunosuppression mice. The level of the cytokine IL-10 in sera of cyclophosphamide-induced mice was decreased after pretreatments of polysaccharides. Flow cytometry results showed that pretreatments with polysaccharides enhanced the phagocytosis of peritoneal macrophages in mice. The increased levels of serum antibody IgG and IgM were observed in the groups pretreated with polysaccharides. Our work demonstrated that the treatment of polysaccharides elicited strong immune activity and a protective effect against cyclophosphamide-induced immunosuppression.

In vivo immunoprotective role of Indigofera tinctoria and Scoparia dulcis aqueous extracts against chronic noise stress induced immune abnormalities in Wistar albino rats

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Chronic noise stress was suppressed both innate and adaptive immune response of wistar albino rats.

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Noise stress also caused DNA damage in the liver and spleen tissues.

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Aqueous extracts of I. tinctoria and S. dulcis prevent the immune abnormalities caused by noise stress.

Indigofera tinctoria and Scoparia dulcis are being widely used in Indian folk medicine for the treatment of various disorders. Environmental noise pollution is thought to be an important factor for many health problems and it causes immune abnormalities. In the present study immune-regulating potential of I. tinctoria and S. dulcis aqueous extracts on innate and adaptive immune system of wistar albino rats was evaluated during normal and chronic noise induced stress conditions. The results demonstrated that both I. tinctoria and S. dulcis aqueous extracts (200 mg/kg b.w) showed immunostimulant effect on both innate and adaptive immune response of wistar albino rat compared to control group under normal condition. The noise stress (100 dB for 1 h, 20 days) induced animals showed suppressive effects on immune response by decreasing macrophage phagocytosis, antibody secretion by spleen cells, humoral immune response, proliferation of lymphocytes, cytotoxicity, TNF α expression, granzyme B and perforin expression in splenic NK cells. Similarly, noise stress also caused DNA damage in tissues. However, the suppressed effects induced by noise stress on rat immune system were significantly prevented by oral administration of both I. tinctoria and S. dulcis aqueous extracts. Considering all these results it is suggested that the selected medicinal plant’s aqueous extracts have the potential to prevent the effects of noise stress induced rat immune system and explore a strong immunostimulant potential applicable to clinical practices.

Dietary Chlorella vulgaris Ameliorates Altered Immunomodulatory Functions in Cyclophosphamide-Induced Immunosuppressive Mice

Based on the well-known toxicity of cyclophosphamide (CYP) on the immune system, this research investigated the modulating effects of the long-term dietary Chlorella vulgaris (CV) supplementation on the immunosuppression induced by CYP in mice, in order to provide a novel dietary design to mitigate the side effects of CYP therapy. Control, CYP-treated, CYP + CV (6%), CYP + CV (12%) and CYP + CV (24%) were used for 6 weeks, CV supplement in diet recovered the significantly reduced immunological function in CYP treated mice. As CV may have a modulating function through the inducible expression of cytokines, we assayed the expressions of interleukin-2 (IL-2), interleukin-12 (IL-12), tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). Our results suggested that CYP significantly reduced the lymphocytes proliferation and phagocytic activities of macrophages, and stimulated the production of IL-2, IL-12, TNF-α and IFN-γ and that this impairment has been successfully adjusted by CV supplementation. Treatment with the algae also enhanced the natural killer (NK) cells cytotoxicity, and ameliorate histological changes of the spleen in CYP-treated mice. Therefore, as we found in this study, a diet supplemented with whole CV has beneficial effects on CVP-induced immunosuppression, through its immunomodulatory potential.