Polysaccharide of Atractylodes macrocephala Koidz (PAMK) Relieves Immunosuppression in Cyclophosphamide-Treated Geese by Maintaining a Humoral and Cellular Immune Balance

Immunomodulatory effect of Atractylodis macrocephala Koidz. polysaccharides in vitro

Vaccination is still the main method of preventing most infectious diseases, but there are inefficiencies and inaccuracies in immunization. Studies have reported that Atractylodis macrocephalae Koidz. polysaccharides (RAMP) have immunomodulatory effects, but the mechanisms involved in whether they can modulate the immune response in chickens are not yet clear. The aim of this study was to investigate the effect of RAMP on lymphocytes functions by analyzing cell proliferation, cell cycle, mRNA expression of cytokines and CD4 +/CD8 + ratio. To identify potential molecules involved in immune regulation, we performed a comprehensive transcriptome profiling of chicken lymphocytes. In addition, the adjuvant effect of RAMP was evaluated by detecting indicators of hemagglutination inhibition. When lymphocytes were cultured with RAMP in vitro, the proliferation rate of lymphocytes was increased (P < 0.01), more cells in S phase and G2/M phase (P < 0.01) and the mRNA expression of IFN-γ was upregulated (P < 0.05), while the mRNA expression of TGF-β (P < 0.01) and IL-4 (P < 0.05) was downregulated and the CD4 +/CD8 + ratio was increased (P < 0.05). Transcriptomic results showed that RAMP increased the expression of HIST1H46 (P < 0.05) and CENPP (P < 0.05). Validation of qPCR showed that RAMP may play an important role in regulating cellular immunity by downregulating the Notch pathway. The results also showed that RAMP could increase the serum Newcastle disease virus antibody levels in chickens. These data suggest that RAMP could enhance immune function of lymphocytes and was a candidate vaccine adjuvant in chickens.

The Mechanisms of Polysaccharides from Tonic Chinese Herbal Medicine on the Enhancement Immune Function: A Review

Tonic Chinese herbal medicine is a type of traditional Chinese medicine, and its primary function is to restore the body's lost nutrients, improve activity levels, increase disease resistance, and alleviate physical exhaustion. The body's immunity can be strengthened by its polysaccharide components, which also have a potent immune-system-protecting effect. Several studies have demonstrated that tonic Chinese herbal medicine polysaccharides can improve the body's immune response to tumor cells, viruses, bacteria, and other harmful substances. However, the regulatory mechanisms by which various polysaccharides used in tonic Chinese herbal medicine enhance immune function vary. This study examines the regulatory effects of different tonic Chinese herbal medicine polysaccharides on immune organs, immune cells, and immune-related cytokines. It explores the immune response mechanism to understand the similarities and differences in the effects of tonic Chinese herbal medicine polysaccharides on immune function and to lay the foundation for the future development of tonic Chinese herbal medicine polysaccharide products.

Research progress on the mechanisms underlying poultry immune regulation by plant polysaccharides

With the rapid development of poultry industry and the highly intensive production management, there are an increasing number of stress factors in poultry production. Excessive stress will affect their growth and development, immune function, and induce immunosuppression, susceptibility to a variety of diseases, and even death. In recent years, increasing interest has focused on natural components extracted from plants, among which plant polysaccharides have been highlighted because of their various biological activities. Plant polysaccharides are natural immunomodulators that can promote the growth of immune organs, activate immune cells and the complement system, and release cytokines. As a green feed additive, plant polysaccharides can not only relieve stress and enhance the immunity and disease resistance of poultry, but also regulate the balance of intestinal microorganisms and effectively alleviate all kinds of stress faced by poultry. This paper reviews the immunomodulatory effects and molecular mechanisms of different plant polysaccharides (Atractylodes macrocephala Koidz polysaccharide, Astragalus polysaccharides, Taishan Pinus massoniana pollen polysaccharide, and alfalfa polysaccharide) in poultry. Current research results reveal that plant polysaccharides have potential uses as therapeutic agents for poultry immune abnormalities and related diseases.

Polysaccharide of Atractylodes macrocephala Koidz Alleviates Cyclophosphamide-Induced Thymus Ferroptosis in Gosling

The present study aimed to explore the mechanism by which PAMK alleviates cyclophosphamide (CTX)-induced ferroptosis in thymocytes. One-day-old goslings were divided into four groups (10 goslings/group). The CON and CTX groups were fed a basic diet. The PAMK and CTX + PAMK groups were fed the basic diet mixed with PAMK (400 mg/kg). Moreover, the CTX and CTX + PAMK groups were given a daily injection of 40 mg/kg BW of CTX (at 19, 20, and 21 days of age). On the other hand, the CON and PAMK groups were given 0.5 mL of sterilized saline into the leg muscle (at 19, 20, and 21 days of age). The goslings were fed for 28 days. The ferroptosis pathway was enriched in transcriptome sequencing. Compared to the CON group, the thymus in the CTX group underwent injury, and the mitochondria of thymocytes showed features of ferroptosis. PAMK treatment alleviated ferroptosis in thymocytes and thymus injury, and CTX-induced elevated levels of oxidative stress and iron content restored GPX4 protein expression (p < 0.05) and inhibited the CTX-induced activation of the ferroptosis pathway (p < 0.05). Conclusively, PAMK could reduce thymus injury by alleviating CTX-induced thymocyte ferroptosis in gosling to alleviate the immunosuppression caused by CTX in the organism.

Condensed Fuzheng extract increases immune function in mice with cyclophosphamide-induced immunosuppression

Our general purpose was to examine the effect of condensed Fuzheng extract (CFE) on the alleviation of immunosuppression. A mouse model of immunosuppression was established by intraperitoneal injection of CTX. A healthy control group received no CTX and no CFE; different intragastric doses of CFE were administered to three groups of mice for 28 days (4500, 2250, or 1125 mg/kg/day); a negative control received CTX alone, and a positive control received CTX and levamisole hydrochloride. We evaluated the effects of CFE on the immune system organs, cells, and molecules by comparing the different groups. CFE significantly improved immune system organs (spleen and thymus indices and histology), stimulated immune cell activities (number of white blood cells and lymphocytes, phagocytosis of mononuclear phagocytes, proliferation of splenic lymphocytes, antibody formation, and NK cell activity), and increased the levels of immunoglobulins (IgA, IgG, and IgM) and cytokines (IL-2 and IFN-γ). Thus CFE effectively alleviated CTX-mediated immunosuppression and oxidative stress and enhanced the immunological functions of mice.

Isolation, structure and bioactivity of polysaccharides from Atractylodes macrocephala: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Polysaccharides from Atractylodes macrocephala are important components isolated and extracted from the traditional Chinese medicine named Atractylodes macrocephala Koidz. Traditionally, A. macrocephala has been used to strengthen the spleen, benefit qi, dry dampness and promote water circulation, and prevent miscarriage. As the main components, polysaccharides from A. macrocephala have a variety of related pharmacological activities, such as the ability to regulate the gastrointestinal tract, protect the liver and so on.

AIM OF THE REVIEW

This review aims to compile the extraction and purification methods, structural characteristics and pharmacological activities of polysaccharides from A. macrocephala and the mechanisms of actions to explore the future application potential of polysaccharides from A. macrocephala.

MATERIALS AND METHODS

Valid and comprehensive relevant information was collected from China National Knowledge Infrastructure, Web of Science, Pubmed and so on.

RESULTS

More than 20 polysaccharides have been extracted from A. macrocephala, different extraction and purification methods have been described, and the composition structures and pharmacological activities of polysaccharides from A. macrocephala have been reviewed. Polysaccharides, as important components of A. macrocephala, were mainly extracted by four methods such as water decoction, ultrasonic-assisted extraction, complex enzyme method and microwave-assisted extraction, and then were obtained through decolorization, deproteinization and separation and purification by various chromatographic columns. The chemical compositions and structures of polysaccharides from A. macrocephala show diversification, and three structural formulae have been confirmed at this stage. Polysaccharides from A. macrocephala have a variety of pharmacological activities, such as immunomodulation, antitumor, antioxidant, hepatoprotection, gastrointestinal mucosa protection, neuroprotection, hypoglycemia, growth promotion and so on.

CONCLUSIONS

There is a diversity in the compositional structures of polysaccharides from A. macrocephal, which have multiple biological activities and promising applications. Therefore, further understanding of the relationship between structures and functions of polysaccharides from A. macrocephaly, and potential synergistic effects with other substances is especially important for its development and utilization.

Effects of PAMK on lncRNA, miRNA, and mRNA expression profiles of thymic epithelial cells

Polysaccharides from Atractylodes macrocephala Koidz (PAMK) can promote the proliferation of thymocytes and improve the body's immunity. However, the effect of PAMK on thymic epithelial cells has not been reported. Studies have shown that miRNAs and lncRNAs are key factors in regulating cell proliferation. In this study, we found that PAMK could promote the proliferation of mouse medullary thymic epithelial cell line 1 (MTEC1) cells through CCK-8 and EdU experiments. To further explore its mechanism, we detected the effect of PAMK on the expression profiles of lncRNAs, miRNAs, and mRNAs in MTEC1 cells. The results showed that PAMK significantly affected the expression of 225 lncRNAs, 29 miRNAs, and 800 mRNAs. Functional analysis showed that these differentially expressed genes were significantly enriched in cell cycle, cell division, NF-kappaB signaling, apoptotic process, and MAPK signaling pathway. Finally, we used Cytoscape to visualize lncRNA-miRNA-mRNA(14 lncRNAs, 17 miRNAs, 171 mRNAs) networks based on ceRNA theory. These results suggest that lncRNAs and miRNAs may be involved in the effect of PAMK on the proliferation of MTEC1 cells, providing a new research direction for exploring the molecular mechanism of PAMK promoting the proliferation of thymic epithelial cells.

The chemistry and efficacy benefits of polysaccharides from Atractylodes macrocephala Koidz

Atractylodes macrocephala Koidz (AM), traditional Chinese medicine (TCM) with many medicinal values, has a long usage history in China and other oriental countries. The phytochemical investigation revealed the presence of volatile oils, polysaccharides, lactones, flavonoids, and others. The polysaccharides from AM are important medicinal components, mainly composed of glucose (Glc), galactose (Gal), rhamnose (Rha), arabinose (Ara), mannose (Man), galacturonic acid (GalA) and xylose (Xyl). It also showed valuable bioactivities, such as immunomodulatory, antitumour, gastroprotective and intestinal health-promoting, hepatoprotective, hypoglycaemic as well as other activities. At the same time, based on its special structure and pharmacological activity, it can also be used as immune adjuvant, natural plant supplement and vaccine adjuvant. The aim of this review is to summarize and critically analyze up-to-data on the chemical compositions, biological activities and applications of polysaccharide from AM based on scientific literatures in recent years.

Polysaccharides from Rhizoma Atractylodis Macrocephalae: A Review on Their Extraction, Purification, Structure, and Bioactivities

Rhizoma Atractylodes macrocephala polysaccharide (RAMP), the main bioactive compound extracted from Rhizoma Atractylodes macrocephala (RAM), exhibits various biological activities in in vivo and in vitro methods, such as anti-inflammatory, antioxidant, antitumor, immunomodulatory, hepatoprotective effects, and other functions. This review systematically summarizes the recent research progress on the extraction, purification, structural characteristics, and biological activities of RAMP. We hope to provide a theoretical basis for further research on the application of RAMP in the fields of biomedicine and food.

Protective Effect of Poria Cocos Polysaccharides on Fecal Peritonitis-Induced Sepsis in Mice Through Inhibition of Oxidative Stress, Inflammation, Apoptosis, and Reduction of Treg Cells

This study was conducted to investigate the potential pharmacological effects of Poria cocos polysaccharides (PCPs) on fecal-induced peritonitis (FIP) mice. Consequently, the fecal peritonitis (FP)-induced septic mice with the higher levels of tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), IL-1β, malondialdehyde (MDA), myeloperoxidase (MPO), histopathological lesion and bacterial burden, and lower levels of superoxide dismutase (SOD) and glutathione (GSH). Interestingly, PCP pre-treatment reduced inflammatory cytokines and oxidative stress in plasma and spleen and improved the resistance to FIP. Inflammatory infiltration and cell death in thymus or splenic tissue were alleviated with PCP pretreatment. Furthermore, Treg cells were moderated in the spleen with PCP pre-administration. In addition, PCP pretreatment downregulated Annexin-V in the thymus of FP-induced septic mice, and apoptosis of splenic cells was dose-dependent. In conclusion, PCPs have pharmacological and biological effects on FP-induced septic mice, and its molecular mechanism is related to antioxidative, anti-inflammation, anti-apoptosis, and the reduction of Treg activity in splenic cells.

Lipopolysaccharide-induced Splenic Ferroptosis in Goslings was Alleviated by Polysaccharide of Atractylodes macrocephala Koidz Associated with Pro-inflammatory Factors

Ferroptosis is a newly discovered form of cell death due to iron-dependent lipid peroxidation. In animal breeding, many environmental factors could lead to oxidative stress, which in turn reduce animal immunity and production performance. Polysaccharide of Atractylodes macrocephala Koidz (PAMK) has antioxidation, immunomodulatory, and inflammatory modulating effects. For investigating the effect of PAMK on splenic ferroptosis in gosling caused by lipopolysaccharide (LPS), 40 one-day-old Magang goslings were randomly divided into 4 groups (CON group, LPS group, PAMK group, and LPS+PAMK group). The protein expression of the ferroptosis marker Glutathione Peroxidase 4 (GPX4), the relative mRNA expression of ferroptosis-related genes and cytokines, and the oxidative stress and iron content of spleen tissues were examined. The correlation between ferroptosis and inflammatory factors was further analyzed by principal component analysis. The results showed that, compared with CON group, LPS caused alterations in the expression of the ferroptosis pathway genes and cytokines, which could upregulate levels of ferroptosis and inflammation. However, after treated with PAMK, the inflammation and ferroptosis was alleviated. Meanwhile, PAMK restored the expression and distribution of GPX4. In addition, PAMK alleviated the oxidative stress caused by LPS and reduced the iron content in spleen. Principal component analysis showed that cytokines were more closely related to antioxidant indexes. The CON, PAMK and LPS+PAMK groups had similar effects on the four components, with the LPS and PAMK groups showing the furthest difference in results. The result indicated that PAMK could reduce the level of oxidative stress and inflammatory cytokines in spleen of gosling caused by LPS, and jointly alleviate ferroptosis by regulating genes related to the ferroptosis pathway.

Polysaccharide of Atractylodes macrocephala Koidz regulates LPS-mediated mouse hepatitis through the TLR4-MyD88-NFκB signaling pathway

Feed corruption and poor breeding environment could cause widespread bacterial infection which could cause severe liver inflammation and lead to liver damage, even death. It has been proved that Polysaccharide of Atractylodes macrocephala Koidz (PAMK) could improve the immunity of animal, but the mechanism of its protective effect on hepatitis has been rarely reported. This study investigated the protective effect of PAMK on mouse liver through LPS-induced liver inflammatory. The results showed that LPS caused swelling of hepatocytes, disappearance of hepatic cord structure and infiltration of a large number of inflammatory cells, and LPS could up-regulated mRNA and protein expression levels of TLR4, MyD88, IKBα and NFκB, increased cytokines IL-1β, IL-4, IL-6 and TNF-α levels, enhance the levels of antioxidant enzymes CAT, GSH-PX, SOD, iNOs and MDA. PAMK pretreatment could relieved histopathological damage caused by LPS, and could activate the TLR4-MyD88-NFκB signalling pathway, reduce the levels of IL-1β, IL-6 and TNF-α, increase IL-4 levels, inhibit the levels of GSH-PX and MDA. These results indicate that PAMK could reduce inflammatory damage and oxidative stress in mice and play a protective role in the early stages of LPS invasion of the liver.

PAMK Relieves LPS-Induced Enteritis and Improves Intestinal Flora Disorder in Goslings

Polysaccharide of Atractylodes macrocephala Koidz (PAMK) is a biologically active component of Atractylodes macrocephala, which has the effect of maintaining the immune homeostasis of the body. Therefore, this study constructed a model of PAMK to relieve LPS-induced gosling enteritis and observed the morphological changes of the small intestine after HE staining. ELISA was used to detect serum CRP, IL-1β, IL-6, and TNF-α levels; immunohistochemistry was used to detect the positive rate of IgA in the small intestine; TLR4, occludin, ZO-1, cytokines, and immunoglobulin mRNA expression in the small intestine were detected by qPCR; and intestinal flora of gosling excrement was analyzed by 16S rDNA sequencing to analyze the protective effect of PAMK on goslings enteritis and the impact on intestinal flora. The results showed that PAMK relieves LPS-induced gosling enteritis by maintaining the small intestine morphology, cytokine, tight junctions, and immunoglobulin relatively stable and improving the disorder of intestinal flora.

Protective effect of the new prepared Atractylodes macrocephala Koidz polysaccharide on fatty liver hemorrhagic syndrome in laying hens

Fatty liver hemorrhage syndrome (FLHS) is the most common noninfectious cause of death in backyard chickens worldwide, which can cause a sudden drop in egg production in the affected flocks and cause huge losses to the laying hens breeding industry. In this study, we prepared polysaccharide from Atractylodes macrocephala Koidz (PAMK) by one-step alcohol precipitation. The structural analysis found that PAMK with a molecular weight of 2.816 × 10³ Da was composed of glucose and mannose, in a molar ratio of 0.582 to 0.418. Furthermore, we investigated the hepatoprotective effects of PAMK on high-energy and low-protein (HELP) diet-induced FLHS in laying hens. The results showed that the hens' livers of the HELP diet showed yellowish-brown, greasy, and soft, whereas the supplement of PAMK (200 mg/kg or 400 mg/kg) could alleviate such pathological changes. The liver index, the abdominal fat percentage, and liver injury induced by the HELP diet were reduced in PAMK (200 mg/kg or 400 mg/kg). Supplementing 200 mg/kg or 400 mg/kg PAMK showed improvements of the antioxidant capacity in laying hens. Furthermore, we found that the HELP diet increased the expression of hepatic lipogenesis genes and decreased the expression of fatty acid β-oxidation genes, which could be reversed by 200 mg/kg or 400 mg/kg PAMK supplementation. Nevertheless, there is no difference between the addition of 40 mg/kg PAMK and the HELP group. Collectively, these results showed that PAMK supplements could ameliorate HELP diet-induced liver injury through regulating activities of antioxidant enzymes and hepatic lipid metabolism. Therefore, PAMK could be a potential feedstuff additive to alleviate FLHS in laying hens.

Polysaccharide of Atractylodes macrocephala Koidz (PAMK) Alleviates Cyclophosphamide-induced Immunosuppression in Mice by Upregulating CD28/IP3R/PLCγ-1/AP-1/NFAT Signal Pathway

The polysaccharide of Atractylodes macrocephala Koidz (PAMK) is recognized as an immune enhancer, with anti-cancer, anti-tumour, lymphocyte-activating and lymphocytes proliferation-inducing effects. For investigating the mechanism that PAMK alleviates the decline in T cell activation induced by CTX, 24 6-week-old BALB/c female mice were randomly divided into four groups (C, PAMK, CTX, PAMK + CTX). The spleen index, splenocytes morphology and death, cytokine concentration, T cell activating factors (CD25, CD69, CD71), mRNA expression levels related to the CD28 signal pathway were detected. Furthermore, the lymphocytes of mice was isolated and cultured, and then the Th1/Th2 ratio, activating factors, mRNA levels related to the CD28 signal pathway were detected. The results showed that PAMK significantly improved the spleen index, alleviated abnormal splenocytes morphology and death, maintained the balance of Th1/Th2 cells, increased the levels of IL-2, IL-6, TNF-α, and IFN-γ, and increased the mRNA levels of CD28, PLCγ-1, IP3R, NFAT, and AP-1. In conclusion, PAMK increased cytokines levels and alleviated the decline in activation level of lymphocytes induced by CTX through CD28/IP3R/PLCγ-1/AP-1/NFAT signal pathway.

Mulberry leaf polysaccharide supplementation contributes to enhancing the respiratory mucosal barrier immune response in Newcastle disease virus-vaccinated chicks

Despite high global vaccination coverage, Newcastle disease (ND) remains a constant threat to poultry producers owing to low antibody levels. Given the respiratory mucosa is the important site for Newcastle disease virus (NDV) vaccination, enhancing respiratory mucosal immunity may help control ND. Our previous study showed that mulberry leaf polysaccharide (MLP) is very promising in delivering a robust balanced immune response, but the effects of it on respiratory immunity in chicks are unknown. In this study, we evaluated the potential of MLP to activate respiratory mucosal immunity and revealed the possible mechanism of MLP as an immunopotentiator for ND vaccines. Chicks were randomly divided into 5 groups: blank control, vaccination control (VC), and low-, middle-, and high-dose MLP (MLP-L, MLP-M, and MLP-H) (n = 30). The serum results of humoral and cell-mediated immune responses showed significant increases in NDV hemagglutination inhibition antibody titer, IgG and IgA antibody levels, and the T-lymphocyte population in the MLP-M group compared with the VC group. Validation of results also indicated remarkable increases in tracheal antibody-mediated immunity and a mucosal immune response in the MLP-M group. Furthermore, the upregulation of TLR7 revealed a possible mechanism. Our findings provided evidence to consider MLP as a potential mucosal vaccine adjuvant candidate against ND in chickens.

Ascorbic Acid Derivative 2-O-β-d-Glucopyranosyl-l-Ascorbic Acid from the Fruit of Lycium barbarum Modulates Microbiota in the Small Intestine and Colon and Exerts an Immunomodulatory Effect on Cyclophosphamide-Treated BALB/c Mice

2-O-β-d-Glucopyranosyl-l-ascorbic acid (AA-2βG) is a natural and stable ascorbic acid derivative isolated from the fruits of Lycium barbarum. In our present study, cyclophosphamide (Cy) was used to make BALB/c mice immunosuppressive and AA-2βG was used to intervene immunosuppressive mice. It was found that Cy treatment resulted in a series of changes on basic immune indexes including a decrease of thymus and spleen indexes and levels of pro-inflammatory cytokines and destruction of leucocyte proportion balance, accompanied with weight loss, reduction in colon length, and changes of hepatic function markers. However, all these changes were reversed in varying degrees by AA-2βG intervention. Notably, AA-2βG could significantly change both mouse colonic and small-intestinal microbiota. The key responsive taxa found in a mouse colon were Muribaculaceae, Ruminococcaceae, Oscillibacter, Rikenella, Helicobacter, Negativibacillus, Alistipes, and Roseburia, and the key responsive taxa found in a mouse small intestine were Muribaculaceae, Anaerotruncus, and Paenibacillus. The results demonstrated that AA-2βG could modulate microbiota in the small intestine and colon and exert an immunomodulatory effect. Further studies should focus on the degradation pathways of AA-2βG and the interaction between AA-2βG and Muribaculaceae.

Selenium-Alleviated Hepatocyte Necrosis and DNA Damage in Cyclophosphamide-Treated Geese by Mitigating Oxidative Stress

Selenium (Se) has been well recognized as an immune-enhancing agent with antioxidant and anti-tumor properties. The commonly used chemotherapy drug, cyclophosphamide (CTX), induces liver injury by increasing the reactive oxygen species (ROS) level. However, little is known about how Se alleviates CTX-induced liver injury in geese. In this study, 90 male Magang geese (3 days old) were randomly allocated into three groups (control, CTX, and Se + CTX group) with three replicates per group and ten geese per replicate. The control and CTX groups were fed a basal diet (Se content was 0.03 mg/kg). The Se + CTX group was fed a basal diet containing 0.44 mg/kg sodium selenite (Se content was 0.2 + 0.03 mg/kg). The control group was injected with 0.5 mL saline, while the CTX and Se + CTX groups were injected with CTX at 40 mg/kg body weight per day on days 21-23. The liver index, liver histology, and ultra-micromorphology detected antioxidant enzyme activity in the liver and serum. In addition, we detected the liver marker enzymes and protein levels in serum, and hepatocyte DNA damage. Se could alleviate liver development dysregulation, hepatocyte structural damage, the disturbances in antioxidant enzyme (GPx, CAT, and SOD) activity, and malondialdehyde (MDA) levels in the serum and liver. Besides, Se could alleviate the dysregulation of liver marker enzyme (ALT and AST) activity and protein (ALB and TP) levels in the serum, and DNA migration induced by CTX. In conclusion, Se may inhibit hepatocyte necrosis and DNA damage by inhibiting CTX-induced oxidative stress.

Atractylodes macrocephala polysaccharides regulate the innate immunity of colorectal cancer cells by modulating the TLR4 signaling pathway

Background

It has been well-recognized that the polysaccharides from Atractylodes macrocephala (PAM) are immune system enhancers, which can facilitate the proliferation of lymphocytes and stimulate immune cells. Nevertheless, the antitumor effects of PAM and their molecular mechanisms remain unclear.

Aim

Our research aimed to evaluate the anti-cancer effects of PAM on colorectal cancer (CRC).

Methods

We tested the effects of PAM on the growth and proliferation of CRC cells and macrophages by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The pro-inflammatory cytokines expression and secretion was analyzed by real-time RT-PCR and ELISA assay. We also used MC38 cells xenograft model to test the anti-cancer effects of PAM in vivo.

Results

We found that although PAM treatment did not significantly affect the growth of CRC cells or enhance the proliferation of bone marrow-derived macrophages (BMDMs), it could enhance the phagocytosis of BMDMs by CRC cells. Biochemical tests and immunoblotting assays revealed that exposing BMDMs to PAM promoted the production of interleukin-6 (IL-6), interferon λ (IFN λ), tumor necrosis factor α (TNF-α), and nitric oxide (NO) through the MyD88/TLR4-dependent signaling pathway. One noteworthy observation is that PAM treatment could significantly prevent tumorigenesis of MC38 cells in C57BL/6J mice and increase the survival duration of mice with tumors, without influence on the weight of those mice. However, the anti-cancer effects of PAM were compromised in TLR4 KO mice, further suggesting that TLR4 signaling plays a vital role in the anti-cancer effects of PAM.

Conclusion

Therefore, PAM may prove to be a potential candidate in cancer immunotherapy.

Decreased number of CD19+CD24hiCD38hi regulatory B cells in Diabetic nephropathy

BACKGROUND

Regulatory B cells participate in the pathogenesis of autoimmune disease. This study aimed to examine the putative contribution of regulatory B cells to the pathogenesis of DN. The number of circulating CD19⁺CD24^hiCD38^hi B cells, CD19⁺CD24^hiCD38^hiCD5⁺ B cells, and CD19⁺CD24^hiCD38^hiIL-10⁺ B cells were significantly lower in DN patients (p < 0.05) than the control group. The number of circulating CD19⁺CD24^hiCD38^hi B cells was positively correlated with the levels of eGFR and serum IL-10 levels, but negatively correlated with urinary protein levels in DN patients. Treatment significantly increased the number of CD19⁺CD24^hiCD38^hi B cells, CD19⁺CD24^hiCD38^hiCD5⁺ B cells, CD19⁺CD24^hiCD38^hiIL-10⁺ B cells, and the levels of serum IL-10 (p < 0.05). We conclude that regulatory B cells may present new targets for intervention of DN.

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.