Inonotus obliquus polysaccharide protects against adverse pregnancy caused by Toxoplasma gondii infection through regulating Th17/Treg balance via TLR4/NF-κB pathway

Immune Cells and Infectious Diseases in Preeclampsia Susceptibility

Preeclampsia is a severe pregnancy disorder, affecting approximately 10% of pregnancies worldwide, characterised by hypertension and proteinuria after the 20th week of gestation. The condition poses significant risks to both maternal and fetal health, including cardiovascular complications and impaired fetal development. Recent trends indicate a rising incidence of preeclampsia, correlating with factors such as advanced maternal age and cardiovascular comorbidities. Emerging evidence also highlights a notable increase in the association between autoimmune and infectious diseases with preeclampsia. Autoimmune conditions, such as type 1 diabetes and systemic lupus erythematosus, and infections triggered by global health challenges, including leptospirosis, Zika, toxoplasmosis, and Chagas disease, are now recognised as significant contributors to preeclampsia susceptibility by affecting placental formation and function. This review focuses on the immunologic mechanisms underpinning preeclampsia, exploring how immune system dysregulation and infectious triggers exacerbate the condition. It also discusses the pathologic mechanisms, including galectins, that preeclampsia shares with autoimmune and infectious diseases, and their significant risk for adverse pregnancy outcomes. We emphasise the necessity for accurate diagnosis and vigilant monitoring of immune and infectious diseases during pregnancy to optimise management and reduce risks. By raising awareness about these evolving risks and their impact on pregnancy, we aim to enhance diagnostic practices and preventive strategies, ultimately improving outcomes for pregnant women, especially in regions affected by environmental changes and endemic diseases.

Shoutai Wan treatment upregulates the expression of TNFAIP3 and improves T cell immune tolerance at maternal-fetal interface

Shoutai Wan (STW) is a traditional Chinese medicine formula used to treat various conditions. The objective of this study was to evaluate the impact of STW on the abortion rate in the URSA mouse model and elucidate its underlying molecular mechanisms. Female CBA/J mice were mated with male DBA/2 mice to establish the URSA model. Network pharmacological analysis was employed to investigate the potential molecular mechanisms of STW. Hematoxylin-eosin staining, immunofluorescence, and ELISA were performed to examine placental microenvironmental changes, protein expression related to TNFAIP3 and the NF-κB signaling pathway. Treatment with STW reduced the abortion rate in URSA model mice and improved trophoblast development. TNFAIP3 was identified as a potential target of STW for treating URSA, as STW enhanced TNFAIP3 protein expression while decreasing IL-6 and TNF-α secretion in the placenta. Moreover, STW upregulated TNFAIP3 protein expression and Foxp3 mRNA levels, increased the production of anti-inflammatory cytokines such as IL-10 and TGF-β1, and decreased p-NF-κB expression in CD4+ cells at the placenta. The findings of this study indicate that STW treatment reduces the abortion rate in the URSA mouse model. These effects are likely mediated by increased TNFAIP3 expression and decreased NF-κB signaling pathway activity at the maternal-fetal interface. These molecular changes may contribute to the regulation of T cell immunity and immune tolerance during pregnancy.

The circAno6/miR-296-3p/TLR4 signaling axis mediates the inflammatory response to induce the activation of hepatic stellate cells

BACKGROUND

Circular RNA (circRNA) is a novel functional non-coding RNA(ncRNA) that plays a role in the occurrence and development of multiple human liver diseases, including liver fibrosis (LF). LF is a reversible repair response after liver injury, and the activation of hepatic stellate cells (HSCs) is the core event. However, the regulatory mechanisms by which circRNAs induce the activation of HSCs in LF are still poorly understood. The circAno6/miR-296-3p/toll-like receptor 4 (TLR4) signaling axis that mediates the inflammatory response and causes the activation of HSCs was investigated in this study.

METHODS

First, a circAno6 overexpression plasmid and small interfering RNA were transfected into cells to determine whether circAno6 can affect the function of HSCs. Second, real-time quantitative polymerase chain reaction (RT-qPCR), enzyme-linked immunosorbent assay (ELISA), western blotting (WB) and immunofluorescence (IF) were used to detect the effects of circAno6 plasmid/siRNA transfection on HSC activation indices, inflammatory markers and the circAno6/miR-296-3p/TLR4 signaling axis. The subcellular position of circAno6 was then examined by nucleo-cytoplasmic separation and fluorescence in situ hybridization (FISH). Finally, a luciferase reporter gene assay was used to identify the relationship between circAno6 and miR-296-3p as well as the relationship between miR-296-3p and TLR4.

RESULTS

CircAno6 was considerably upregulated in HSCs and positively correlated with cell proliferation and alpha-smooth muscle actin (α-SMA), collagen I, NOD-likereceptorthermalproteindomainassociatedprotein 3 (NLRP3), interleukin-1β (IL-1β) and interleukin-18 (IL-18) expression. Overexpression of circAno6 increased the inflammatory response and induced HSC activation, whereas interference resulted in the opposite effects. FISH experiments revealed the localization of circAno6 in the cytoplasm. Then, a double luciferase reporter assay confirmed that miR-296-3p significantly inhibited luciferase activity in the circAno6-WT and TLR4-WT groups.

CONCLUSION

This study suggests that circAno6 and miR-296-3p/TLR4 may form a regulatory axis and regulate the inflammatory response, which in turn induces HSC activation. Targeting circAno6 may be a potential therapeutic strategy to treat LF.

Impact of Incorporating Dried Chaga Mushroom (Inonotus obliquus) into Gluten-Free Bread on Its Antioxidant and Sensory Characteristics

Gluten-free bread is increasingly popular among individuals with celiac disease, and The incorporation of mushroom flour offers a novel method to enhance its nutritional profile, antioxidant content, and sensory properties. This study aimed to evaluate the antioxidant and sensory characteristics of gluten-free bread with varying amounts of chaga mushroom flour (5%, 10%, 15%, 20%). The total contents of polyphenols and flavonoids were measured using a spectrophotometric method. Antioxidant activity was assessed through DPPH and FRAP methods, while textural properties were evaluated using the TPA test. Bread colour was analysed using the CIELab system, and sensory evaluation was performed by a panel of trained consumers. The results showed that gluten-free bread enriched with chaga flour had increased polyphenol and flavonoid content and enhanced antioxidant activity. The highest levels of polyphenols, flavonoids, DPPH, and FRAP activity were found in bread with 20% chaga. The addition of chaga mushroom significantly affected the bread's hardness, cohesiveness, and chewiness. Specifically, 20% chaga flour had the most pronounced effect on hardness and elasticity, while 15% chaga flour had the greatest impact on chewiness and cohesiveness. The bread's colour darkened with higher chaga concentrations. The results of sensory evaluation showed a negative correlation between consumer preferences and bread fortified with chaga mushroom flour. The overall consumer acceptability score indicates that only a small addition of mushroom flour (up to 10%) can be used to bake gluten-free bread.

Inhibition of Foxp3 expression in the placenta of mice infected intraperitoneally by toxoplasma gondii tachyzoites: insights into the PPARγ/miR-7b-5p/Sp1 signaling pathway

BACKGROUND

Toxoplasma gondii, an obligate intracellular parasitic protozoa, infects approximately 30% of the global population. Contracting T. gondii at the primary infection of the mother can result in neonatal microcephaly, chorioretinitis, hydrocephalus, or mortality. Our previous study indicated that pregnant mice infected with T. gondii displayed a decrease in both the number and the suppressive ability of regulatory T cells, accompanied by the reduced Forkhead box P3 (Foxp3). Numerous studies have proved that microRNAs (miRNAs) are implicated in T. gondii infection, but there is meager evidence on the relationship between alterations of miRNAs and downregulation of Foxp3 induced by T. gondii.

METHODS

Quantitative reverse transcription polymerase chain reaction was utilized to detect the transcriptions of miRNAs and Foxp3. Protein blotting and immunofluorescence were used to detect the expressions of Foxp3 and related transcription factors. The structure of mouse placenta was observed by hematoxylin and eosin (HE) staining. To examine the activity of miR-7b promoter and whether miR-7b-5p targets Sp1 to suppress Foxp3 expression, we constructed recombinant plasmids containing the full-length/truncated/mutant miR-7b promoter sequence or wildtype/mutant of Sp1 3' untranslated region (3' UTR) to detect the fluorescence activity in EL4 cells.

RESULTS

In T. gondii-infected mice, miR-7b transcription was significantly elevated, while Foxp3 expression was decreased in the placenta. In vitro, miR-7b mimics downregulated Foxp3 expression, whereas its inhibitors significantly upregulated Foxp3 expression. miR-7b promoter activity was elevated upon the stimulation of T. gondii antigens, which was mitigated by co-transfection of mutant miR-7b promoter lacking peroxisome proliferator-activated receptor γ (PPARγ) target sites. Additionally, miR-7b mimics diminished Sp1 expression, while miR-7b inhibitors elevated its expression. miR-7b mimics deceased the fluorescence activity of Sp1 3' untranslated region (3' UTR), but it failed to impact the fluorescence activity upon the co-transfection of mutant Sp1 3' UTR lacking miR-7b target site.

CONCLUSIONS

T. gondii infection and antigens promote miR-7b transcription but inhibit Foxp3 protein and gene levels. T. gondii antigens promote miR-7b promoter activity by a PPARγ-dependent mechanism. miR-7b directly binds to Sp1 3' UTR to repress Sp1 expression. Understanding the regulatory functions by which T. gondii-induced miR-7b suppresses Foxp3 expression can provide new perspectives for the possible therapeutic avenue of T. gondii-induced adverse pregnancy outcomes.

Role of Nrf2/HO-1 pathway on inhibiting activation of ChTLR15/ChNLRP3 inflammatory pathway stimulated by E. tenella sporozoites

The aim of this study is to explore whether Nrf2 antioxidant pathway negatively regulates the ChTLR15/NLRP3 inflammatory pathway stimulated by Eimeria tenella infection. Firstly, levels of molecules in the Nrf2/HO-1 pathway in DF-1 cells pre-treated with an optimized dose of Corilagine or probiotics Levilactobacillus brevis 23017 were quantified using real-time PCR (qRT-PCR) and Western blot. Then, DF-1 cells pre-treated with Corilagine or L. brevis 23017 were stimulated with E. tenella sporozoites, and mRNA levels of molecules in Nrf2/HO-1 and ChTLR15/NLRP3 pathways, protein levels of p-Nrf2, Nrf2, HO-1, ChTLR15 and ChNLRP3, levels of malondialdehyde (MDA) and reactive oxygen species (ROS) were quantified. Further, expression level of Nrf2 and ChTLR15 in DF-1 cells was knocked down by RNA interfering (RNAi) method, and target cells were pre-treated with Corilagine or L. brevis 23017, followed by stimulation with E. tenella sporozoites, and the expression levels of key molecules in Nrf2/HO-1 and ChTLR15/NLRP3 pathways were quantified. The results showed that mRNA and protein levels of key molecules in the Nrf2/HO-1 pathway in DF-1 cells was significantly upregulated after pretreating with 15 μM Corilagine and supernatant of L. brevis 23017. After stimulating with E. tenella sporozoites, levels of molecules in the ChTLR15/NLRP3 pathway, levels of MDA and ROS in DF-1 cells pre-treated with 15 μM Corilagine or bacterial supernatant were all significantly down-regulated. The results from the knock-down experiment also displayed that Corrigine and L. brevis 23017 inhibited the activation of the ChTLR15/ChNLRP3 inflammatory pathway stimulated by E. tenella sporozoites through activating Nrf2/HO-1 antioxidant pathway. This study provides new ideas for the development of novel anticoccidial products.

Research Progress on Application of Inonotus obliquus in Diabetic Kidney Disease

Diabetic kidney disease (DKD) is one of the prime causes of end-stage renal disease. At present, the treatment of DKD is mainly confined to inhibiting the renin-angiotensin-aldosterone system, but the therapeutic effects is not satisfactory. As a kind of very rare and precious medicinal fungi, Inonotus obliquus has a very high medicinal value. Due to its special hypoglycemic and pharmacological effect, researchers currently have attached great importance to it. In this paper, the biological activities, pharmacological effects and application status in the treatment of DKD-related diseases of Inonotus obliquus and the latest progress of metabolites isolated from it in DKD were summarized, thus providing detailed insights and basic understanding of the potential application prospects in DKD.

Modulation of autophagy as a therapeutic strategy for Toxoplasma gondii infection

Toxoplasma gondii infection is a severe health threat that endangers billions of people worldwide. T. gondii utilizes the host cell membrane to form a parasitophorous vacuole (PV), thereby fully isolating itself from the host cell cytoplasm and making intracellular clearance difficult. PV can be targeted and destroyed by autophagy. Autophagic targeting results in T. gondii killing via the fusion of autophagosomes and lysosomes. However, T. gondii has developed many strategies to suppress autophagic targeting. Accordingly, the interplay between host cell autophagy and T. gondii is an emerging area with important practical implications. By promoting the canonical autophagy pathway or attenuating the suppression of autophagic targeting, autophagy can be effectively utilized in the development of novel therapeutic strategies against T gondii. Here, we have illustrated the complex interplay between host cell mediated autophagy and T. gondii. Different strategies to promote autophagy in order to target the parasite have been elucidated. Besides, we have analyzed some potential new drug molecules from the DrugBank database using bioinformatics tools, which can modulate autophagy. Various challenges and opportunities focusing autophagy mediated T. gondii clearance have been discussed, which will provide new insights for the development of novel drugs against the parasite.

An Acidic Polysaccharide with Anti-Inflammatory Effects from Blackened Jujube: Conformation and Rheological Properties

An acidic polysaccharide fraction (BJP-4) was isolated from blackened jujube, and its advanced structures and anti-inflammatory activity were investigated. X-ray diffraction showed that BJP-4 exhibits both crystalline and amorphous portions. Atomic force microscopy data suggested that it contains a large number of spherical lumps. Circular dichroism and Congo red experiments revealed that it has no triple-helix conformation. In steady shear flow results, the BJP-4 solution was a pseudoplastic non-Newtonian fluid with acid-base stability. BJP-4 (20 mg/mL) showed liquid-like properties (G″ > G′), while it performed weak gel-like behavior at a high concentration (40 mg/mL) (G′ > G″). The anti-inflammatory effects of BJP-4 were further evaluated through in vitro experiments. BJP-4 could down-regulate the over-secretion of inflammatory factors (NO, IL-6, IL-1β, TNF-α, iNOS and COX-2) in RAW264.7 cells due to LPS stimulation. Moreover, it demonstrated that BJP-4 restrained the NF-κB signal pathway by regulating TLR4 expression, reducing IκBα phosphorylation level and NF-κB p65 nuclear translocation. In summary, this present study contributes to the application of blackened jujube polysaccharides in the foods and medicine field.

Evaluation of Toxicity and Efficacy of Inotodiol As an Anti-Inflammatory Agent Using Animal Model

Chaga mushroom (Inonotus obliquus) comprises polyphenolic compounds, triterpenoids, polysaccharides, and sterols. Among the triterpenoid components, inotodiol has been broadly examined because of its various biological activities. The purpose of this study is to examine inotodiol from a safety point of view and to present the potential possibilities of inotodiol for medical usage. From chaga mushroom extract, crude inotodiol (INO20) and pure inotodiol (INO95) were produced. Mice were treated with either INO20 or INO95 once daily using oral administration for repeated dose toxicity evaluation. Serum biochemistry parameters were analyzed, and the level of pro-inflammatory cytokines in the serum was quantified. In parallel, the effect of inotodiol on food allergic symptoms was investigated. Repeated administration of inotodiol did not show any mortality or abnormalities in organs. In food allergy studies, the symptoms of diarrhea were ameliorated by administration with INO95 and INO20. Furthermore, the level of MCPT-1 decreased by treatment with inotodiol. In this study, we demonstrated for the first time that inotodiol does not cause any detrimental effect by showing anti-allergic activities in vivo by inhibiting mast cell function. Our data highlight the potential to use inotodiol as an immune modulator for diseases related to inflammation.

Astragalus Polysaccharide Relieves Inflammatory Responses in Guinea Pigs with Allergic Rhinitis via Ameliorating NF-kB-Mediated Treg/Th17 Imbalance

BACKGROUND

Allergic rhinitis (AR) is regarded as a prevalent and non-infectious inflammation in nasal mucosa, and astragalus polysaccharide (APS) could mitigate inflammation.

OBJECTIVES

Herein, this study probed the specific mechanism of APS in inflammatory responses in AR.

METHODS

Firstly, AR guinea pig models were established through the stimulation and sensitization of ovalbumin (OVA) and received APS treatment. Changes in nasal symptoms were assessed through counting the sneezing and rubbing times of guinea pigs. The change patterns of OVA-specific immunoglobulin-E (OVA-sIgE), OVA-specific immunoglobulin-G1 (OVA-sIgG1), tumor necrosis factor (TNF)-α, and interleukin (IL)-6 in guinea pig serum were identified. Meanwhile, the levels of IL-17, transforming growth factor (TGF)-β, IL-10, and forkhead box protein P3 (Foxp3) in the guinea pig tissues or serum were examined, and CD25⁺Foxp3⁺Treg or CD4⁺IL17⁺Th17 cell proportion was detected. Afterwards, nuclear factor-kappa B (NF-kB) expression in guinea pig nasal mucosa tissues were examined. Rescue experiments were designed to probe the role of NF-kB overexpression in inflammatory responses and Treg/Th17 imbalance in AR guinea pigs.

RESULTS

APS treatment reduced sneezing and rubbing times of AR guinea pigs and suppressed OVA-sIgE, OVA-sIgG1, TNF-α, and IL-6 levels in guinea pig serum, and meanwhile, increased CD25⁺Foxp3⁺Treg cell proportion while reduced CD4⁺IL17⁺Th17 cell proportion in AR guinea pig serum or tissues, in a dose-dependent manner. NF-kB was highly-expressed in AR guinea pigs and down-regulated after APS treatment. NF-kB overexpression facilitated inflammatory responses and Treg/Th17 imbalance in AR.

CONCLUSION

APS reduced Treg/Th17 imbalance via suppressing NF-kB expression, thereby ameliorating inflammatory responses in AR.

YYFZBJS inhibits colorectal tumorigenesis by enhancing Tregs-induced immunosuppression through HIF-1α mediated hypoxia in vivo and in vitro

BACKGROUND AND PURPOSE

The occurrence of colorectal cancer (CRC) is associated with a variety of factors. Accumulating evidence shows that peripheral differentiation of regulatory T cells (Tregs) is critical in controlling tumorigenesis. Our previous studies demonstrated that the Yi-Yi-Fu-Zi-Bai-Jiang-San (YYFZBJS) extract exerted potent anticancer activities by significantly enhancing immunosuppression in ApcMin/+ mice. However, there is limited knowledge on the effect of YYFZBJS in the prevention of colorectal cancer and the underlying mechanisms of action.

METHODS

In this study, we investigated the effect of oral administration of YYFZBJS in preventing azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced tumorigenesis. We found that YYFZBJS treatment decreased tumor load, tumor number, histology, and the severity of disease activity index (DAI) scores. To investigate if YYFZBJS inhibited tumorigenesis by regulating regulatory T cells, we depleted Tregs in AOM/DSS mice. We then analyzed the effect of intragastric administration of YYFZBJS on tumorigenesis and the regulation of tumor microenvironment.

RESULTS

As expected, intragastric administration of YYFZBJS in AOM/DSS mice model significantly increased immune responses in the tumor microenvironment through its hypoxia-associated anti-cancer activities. Additionally, YYFZBJS regulated the polarization of peripheral Treg (pTreg) to suppress CRC cell proliferation and infiltration. This was demonstrated by the decrease in tumor proliferation-related proteins including p-STAT3, p-NF-κB and MMPs in a dose-dependent manner. Clinically, the increase in the levels of Tregs in human tissues during CRC progression was associated with low expression of HIF-1α in the stroma, and correlated with CRC survival and prognosis.

CONCLUSION

Altogether, we demonstrated that HIF-1α may promote pTreg -induced carcinogenesis and progression of CRC cells, indicating that YYFZBJS is a promising protective agent against HIF-1α-mediated Treg activation in colorectal cancer. This study is the first to imply a novel clinical significance of a traditional Chinese herbal medicine from Synopsis of Golden Chamber in the cancer treatment and clarify the important role of tumor microenvironment in preventing tumorigenesis.

Oral administration of Lactobacillus brevis 23017 combined with ellagic acid attenuates intestinal inflammatory injury caused by Eimeria infection by activating the Nrf2/HO-1 antioxidant pathway

The aim of this study was to investigate whether oral administration of Lactobacillus brevis 23017 (LB) alone and in combination with ellagic acid inhibits ChTLR15/ChNLRP3/ChIL-1β by activating the Nrf2/HO-1 pathway to attenuate intestinal inflammatory injury. Two animal experiments were performed. In Experiment 1, chickens were allocated into 7 groups: PBS, and low, medium and high dosages of live and heat-killed LB, named L/LB(+), M/LB(+) and H/LB(+), and L/LB(-), M/LB(-) and H/LB(-), respectively. In Experiment 2, chickens were divided into 5 groups: PBS, challenge control, and low, medium and high dosages of ellagic acid combined with LB(+), named L/EA + L/LB(+), M/EA + M/LB(+) and H/EA + H/LB(+), respectively. Chickens were gavaged with LB with or without ellagic acid once a day. Then, the mRNA and protein levels of the components of the Nrf2/HO-1 pathway found in the caecal tissues were quantified. On Day 7 post-infection with E. tenella, the levels of the components of the ChTLR15/NLRP3/IL-1β pathway in the caeca were again quantified, and the anticoccidial effects were assessed. The results showed that the levels of the genes in the Nrf2/HO-1 pathway in the chickens in the LB(+) groups were higher than those in the LB(-) groups (p < 0.001); those in the H/LB(+) group were higher than those in the M/LB(+) and L/LB(+) groups (p < 0.001); and those in the H/EA + H/LB(+) group showed the highest expression levels compared with the other groups (p < 0.001). After challenge, the chickens in the H/LB(+) group displayed less inflammatory injury than those in the M/LB(+) and L/LB(+) groups (p < 0.05), and the chickens in the H/EA + H/LB(+) group showed stronger anti-inflammatory effects than the other groups (p < 0.05). Thus, these protective effects against infection were consistent with the above results. Overall, significant anti-inflammatory effects were observed in chickens orally gavaged with high dosages of live L. brevis 23017 and ellagic acid, which occurred by regulation of the ChTLR15/NLRP3/IL-1β pathway.

Inhibitory Effects of Inonotus obliquus Polysaccharide on Inflammatory Response in Toxoplasma gondii-Infected RAW264.7 Macrophages

Our previous reports have shown that Inonotus obliquus polysaccharide (IOP) has protective effects against Toxoplasma gondii (T. gondii) infection in vivo. The aim of the present research is to explore the in vitro anti-inflammatory effects of IOP and its mechanism in RAW264.7 macrophages infected by T. gondii. In this study, it is indicated that IOP decreased the excessive secretion of inflammatory cytokines tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-1β (IL-1β), IL-4, and IL-6 in T. gondii-infected RAW264.7 macrophages. IOP effectively suppressed the mRNA expression of these cytokines and chemokines monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1α (MIP-1α). Moreover, IOP inhibited the phosphorylation of inhibitor kappa B kinase α/β (IKKα/β), inhibitor κBα (IκBα), p65 in nuclear factor-kappa B (NF-κB) signaling pathway and p38, c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase 1/2 (ERK1/2) in mitogen-activated protein kinases (MAPKs) signaling pathway. Meantime, IOP prevented NF-κB p65 and c-Jun translocation from the cytoplasm to the nucleus. Further, IOP downregulated the protein expression of toll-like receptor 2 (TLR2) and TLR4 in T. gondii-infected RAW264.7 macrophages. The above results suggest that IOP can inhibit the inflammatory response infected with T. gondii via regulating TLR2/TLR4-NF-κB/MAPKs pathways and exerting its anti-T. gondii role in vitro.

Immunomodulatory effects of Inonotus obliquus polysaccharide on splenic lymphocytes infected with Toxoplasma gondii via NF-κB and MAPKs pathways

CONTEXT

As a medicinal and edible fungus, Inonotus obliquus has been traditionally used to prevent and treat various ailments. Inonotus obliquus polysaccharide (IOP) isolated from I. obliquus processes many biological activities, our series of in vivo studies have shown that IOP protects against Toxoplasma gondii infection.

OBJECTIVE

This study aimed to investigate the in vitro immunomodulatory effects and its mechanisms of IOP on mouse splenic lymphocytes infected with T. gondii.

MATERIALS AND METHODS

Mouse splenic lymphocytes were infected with T. gondii tachyzoites, and treated with different concentrations of IOP. The levels of cytokines and chemokines were measured by enzyme-linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR). The expression of toll-like receptor 2 (TLR2) and TLR4, and the modulation of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) signaling pathways were determined by Western blot.

RESULTS

IOP significantly decreased the over-release of cytokine interleukin-1 beta (IL-1β), IL-4, IL-6, interferon-gamma (IFN-γ), and tumor necrosis factor-alpha (TNF-α) in supernatant from T. gondii-infected splenic lymphocytes. IOP also effectively inhibited the overexpression of cytokines and chemokine macrophage inflammatory protein-1 (MIP-1) and monocyte chemoattractant protein-1 (MCP-1) mRNA. Furthermore, IOP down-regulated TLR2 and TLR4 expressions and inhibited the over-phosphorylation of NF-κB p65 and inhibitor κBα (IκBα) in NF-κB signaling pathway and p38, c-Jun N-terminal kinase (JNK) in MAPKs signaling pathway. By observing the effect of IOP on TNF-α secretion after pretreatment with specific inhibitors, it was further confirmed that IOP was involved in the regulation of NF-κB, p38, and JNK signaling pathways.

CONCLUSIONS

These data indicate that IOP can inhibit the excessive inflammatory response caused by T. gondii infection through modulating NF-κB, p38, and JNK signaling pathways, and thus plays the in vitro anti-T. gondii role.

A polysaccharide from natural Cordyceps sinensis regulates the intestinal immunity and gut microbiota in mice with cyclophosphamide-induced intestinal injury

A polysaccharide from Cordyceps sinensis (NCSP) was reported to attenuate intestinal injury and regulate the balance of T helper (Th)1/Th2 cells in immunosuppressed mice. However, whether it influences Th17 and regulatory T (Treg) cells as well as gut ecology remains unknown. In the present study, the intestinal injury mouse model was also established by intraperitoneal injection of cyclophosphamide (Cy) for three consecutive days. NCSP was found to increase the number of CD4⁺ T cells, stimulate the secretion of interleukins (IL)-17 and IL-21, and the expression of transcription factor (retinoic acid-related orphan receptor (ROR)-γt). The levels of transforming growth factor (TGF)-β3 and transcription factor (forkhead box (Fox)p-3) were increased in NCSP-treated groups. Moreover, NCSP upregulated the mRNA expression of toll like receptors (TLR-2, -6 and -9), while it downregulated the TLR-4 expression. In addition, NCSP modulated the intestinal microbiota composition and increased the levels of SCFAs. These findings indicated that NCSP may enhance intestinal immunity and have the potential to become a prebiotic to regulate intestinal microbiota.

Recent Developments in Inonotus obliquus (Chaga mushroom) Polysaccharides: Isolation, Structural Characteristics, Biological Activities and Application

Inonotus obliquus (Chaga mushroom) is a kind of medicine and health food widely used by folk in China, Russia, Korea, and some occidental countries. Among the extracts from Inonotus obliquus, Inonotus obliquus polysaccharide (IOPS) is supposed to be one of the major bioactive components in Inonotus obliquus, which possesses antitumor, antioxidant, anti-virus, hypoglycemic, and hypolipidemic activities. In this review, the current advancements on extraction, purification, structural characteristics, and biological activities of IOPS were summarized. This review can provide significant insight into the IOPS bioactivities as their in vitro and in vivo data were summarized, and some possible mechanisms were listed. Furthermore, applications of IOPS were reviewed and discussed; IOPS might be a potential candidate for the treatment of cancers and type 2 diabetes. Besides, new perspectives for the future work of IOPS were also proposed.

Effects of Taraxacum and Astragalus extracts combined with probiotic Bacillus subtilis and Lactobacillus on Escherichia coli-infected broiler chickens

Diarrhea caused by Escherichia coli (E. coli) is one of the most common diseases that affects the growth and development of poultry. This study was conducted to investigate the synergistic effects of traditional Chinese medicine (TCM) combined with probiotics against E. coli infection and its mechanism in broiler chickens. The optimal proportion formula TCM and probiotics was screened by orthogonal test and range analysis method; the in vitro antibacterial activity was based on the Oxford cup method. Isolated pathogenic E. coli was injected subcutaneously into the neck of the broilers to establish an E. coli-infected model. The broilers were administrated with drugs in drinking water daily for 7 d before and after E. coli infection. The diarrhea rate, mortality, body weight (BW) gain, feed intake, immune organ index, intestinal and hepatic histopathological changes were monitored. The expression of IL-2, IL-10, and TLR-4 mRNA in the intestinal tissues was measured by RT-PCR. Our results showed that the optimal proportion formula of Taraxacum extracts: total flavonoids of Astragalus: polysaccharides of Astragalus: probiotics was 5: 2: 2: 2; TCM combined with probiotics was highly sensitive to E. coli. TCM combined with probiotics synergistically increased BW gain, decreased the diarrhea rate and mortality of broilers, alleviated intestinal and hepatic pathological changes, accompanied by the increase of IL-2 and IL-10 mRNA expression and the inhibition of TLR-4 mRNA expression. It suggests that the combination of TCM and probiotics may produce a synergistic protective effect against E. coli infection by improving the indicators of diarrhea and regulating the expression of IL-2, IL-10, and TLR-4 mRNA in broiler chickens. The synergistic interactions between TCM and probiotics represent a promising strategy for the treatment of E. coli infection.

Deciphering the antitumoral potential of the bioactive metabolites from medicinal mushroom Inonotus obliquus

ETHNOPHARMACOLOGICAL RELEVANCE

The crude extracts of the medicinal mushroom Inonotus obliquus have been used as an effective traditional medicine to treat malicious tumors, gastritis, gastric ulcers, and other inflammatory conditions in Russia and most Baltic countries.

AIM OF THIS REVIEW

Deciphering the antitumoral potential of the bioactive metabolites from I. obliquus and addressing its possibility to be used as effective agents for tumor treatment, restoration of compromised immunity and protection of gastrointestinal damage caused by chemotherapy.

MATERIALS AND METHODS

We analysed the current achievements and dilemma in tumor chemo- or immunotherapy. In this context, we searched the published literatures on I. obliquus covering from 1990 to 2020, and summarized the activities of antitumor, antioxidation, and immunomodulation by the polysaccharides, triterpenoids, small phenolic compounds, and hispidin polyphenols. By comparing the merits and shortcomings of current and traditional methodology for tumor treatment, we further addressed feasibility for the use of I. obliquus as an effective natural drug for tumor treatment and prevention.

RESULTS

The diverse bioactive metabolites confer I. obliquus great potential to inhibit tumor growth and metastasis. Its antitumor activities are achieved either through suppressing multiple oncogenic signals including but not limited to the activation of NF-κB and FAK, and the expression of RhoA/MMP-9 via ERK1/2 and PI3K/Akt signaling pathway. The antitumor activities can also be achieved by inhibiting tyrosinase activity via PAK1-dependent signaling pathway or altering lysosomal membrane permeabilization through blocking tubulin polymerization and/or disturbing energy metabolism through LKB1/AMPK pathway. In addition, the metabolites from I. obliquus also harbour the potentials to reverse MDR either through selective inhibition on P-gp/ABCB1 or MRP1/ABCC1 proteins or the induction of G2/M checkpoint arrest in tumor cells of chemoresistant phenotypes mediated by Nox/ROS/NF-kB/STAT3 signaling pathway. In addition to the eminent effects in tumor inhibition, the metabolites in I. obliquus also exhibit immunomodulatory potential to restore the compromised immunity and protect against ulcerative damage of GI tract caused by chemotherapy.

CONCLUSIONS

I. obliquus possesses the potential to reduce incidence of tumorigenesis in healthy people. For those whose complete remission has been achieved by chemotherapy, administration of the fungus will inhibit the activation of upstream oncogenic signals and thereby prevent metastasis; for those who are in the process of chemotherapy administration of the fungus will not only chemosensitize the tumor cells and thereby increasing the chemotherapeutic effects, but also help to restore the compromised immunity and protect against ulcerative GI tract damage and other side-effects induced by chemotherapy.

The imbalance of the Th17/Treg axis following equine ascending placental infection

Ascending placentitis is a leading cause of abortion in the horse, but adaptive immune response to this disease is unknown. To evaluate this, sub-acute placentitis was experimentally-induced via trans-cervical inoculation of S. zooepidemicus, and endometrium and chorioallantois was collected 8 days later (n = 6 inoculated/n = 6 control). The expression of transcripts relating to Th1, Th2, Th17, and Treg maturation was assessed via RNASeq. IHC of transcription factors relating to each subtype in the same tissues (Th1: TBX21, Th2: GATA3, Th17: IRF4, Treg: FOXp3). An immunoassay was utilized to assess circulating cytokines (Th1: IFNg, IL-2; Th2: IL-4, IL-5; Th17: IL-17, IL-6; Treg: IL-10, GM-CSF). An increase in Th1 and Th17-related transcripts were noted in the chorioallantois, although no alterations were seen in the endometrium. Th2 and Treg-related transcripts altered in a dysregulated manner, as some transcripts increased in expression while others decreased. Immunolocalization of Th1, Th2, and Th17 cells was increased in diseased chorioallantois, while no Treg cells were noted in the diseased tissue. Secreted cytokines relating to Th1 (IFNg, IL-2), Th17 (IL-6), Th2 (IL-5), and Treg (IL-10) populations increased in maternal circulation eight days after inoculation. In conclusion, the Th1/Th17 response to ascending placentitis occurs primarily in the chorioallantois, indicating the adaptive immune response to occur in fetal derived placental tissue. Additionally, ascending placentitis leads to an increase in the helper T cell populations (Th1/Th17/Th2) while decreasing the Treg response. This increase in Th17-related responses alongside a diminishing Treg-related response may precede or contribute to fetal demise, abortion, or preterm labor.

Inonotus obliquus - from folk medicine to clinical use

The Inonotus obliquus (I. obliquus) mushroom was traditionally used to treat various gastrointestinal diseases. For many years, mounting evidence has indicated the potential of I. obliquus extracts for treatment of viral and parasitic infections. Furthermore, substances from I. obiquus have been shown to stimulate the immune system. The most promising finding was the demonstration that I. obliquus has hypoglycemic and insulin sensitivity potential. This review summarizes the therapeutic potential of I. obliquus extracts in counteracting the progression of cancers and diabetes mellitus as well as their antiviral and antiparasitic activities and antioxidant role. As shown by literature data, various authors have tried to determine the molecular mechanism of action of I. obliquus extracts. Two mechanisms of action of I. obliquus extracts are currently emerging. The first is associated with the broad-sense impact on antioxidant enzymes and the level of reactive oxygen species (ROS). The other is related to peroxisome proliferator-activated receptor gamma (PPARγ) effects. This receptor may be a key factor in the anti-inflammatory, antioxidant, and anti-cancer activity of I. obliquus extracts. It can be concluded that I. obliquus fits the definition of functional food and has a potentially positive effect on health beyond basic nutrition; however, studies that meet the evidence-based medicine (EBM) criteria are needed.

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Extracts or polysaccharides from I. obliquus exhibit an anti-cancer potential in vitro.

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Extracts or polysaccharides from I. obliquus exhibit anti-inflammation potential.

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Extracts or polysaccharides from I. obliquus exhibit hypoglycemic and insulin sensitivity potential.

Insight Into TLR4-Mediated Immunomodulation in Normal Pregnancy and Related Disorders

Unlike organ transplants where an immunosuppressive environment is required, a successful pregnancy involves an extremely robust, dynamic, and responsive maternal immune system to maintain the development of the fetus. A specific set of hormones and cytokines are associated with a particular stage of pregnancy. Any disturbance that alters this fine balance could compromise the development and function of the placenta. Although there are numerous underlying causes of pregnancy-related complications, untimely activation of Toll-like receptors (TLR), primarily TLR4, by intrauterine microbes poses the greatest risk. TLR4 is an important Pattern Recognition Receptor (PRR), which activates both innate and adaptive immune cells. TLR4 activation by LPS or DAMPs leads to the production of pro-inflammatory cytokines via the MyD88 dependent or independent pathway. Immune cells modulate the materno–fetal interface by TLR4-mediated cytokine production, which changes at different stages of pregnancy. In most pregnancy disorders, such as PTB, PE, or placental malaria, the TLR4 expression is upregulated in immune cells or in maternal derived cells, leading to the aberrant production of pro-inflammatory cytokines at the materno–fetal interface. Lack of functional TLR4 in mice has reduced the pro-inflammatory responses, leading to an improved pregnancy, which further strengthens the fact that abnormal TLR4 activation creates a hostile environment for the developing fetus. A recent study proposed that endothelial and perivascular stromal cells should interact with each other in order to maintain a homeostatic balance during TLR4-mediated inflammation. It has been reported that depleting immune cells or supplying anti-inflammatory cytokines can prevent PTB, PE, or fetal death. Blocking TLR4 signaling or its downstream molecule by inhibitors or antagonists has proven to improve pregnancy-related complications to some extent in clinical and animal models. To date, there has been a lack of knowledge regarding whether TLR4 accessories such as CD14 and MD-2 are important in pregnancy and whether these accessory molecules could be promising drug targets for combinatorial treatment of various pregnancy disorders. This review mainly focuses on the activation of TLR4 during pregnancy, its immunomodulatory functions, and the upcoming advancement in this field regarding the improvement of pregnancy-related issues by various therapeutic approaches.

Inonotus obliquus polysaccharide ameliorates impaired reproductive function caused by Toxoplasma gondii infection in male mice via regulating Nrf2-PI3K/AKT pathway

This study was carried out to investigate the effects of Inonotus obliquus polysaccharide (IOP) on impaired reproductive function and its mechanisms in Toxoplasma gondii (T. gondii)-infected male mice. Results showed that IOP significantly improved the spermatogenic capacity and ameliorated pathological damage of testis, increased serum testosterone (T), luteinizing hormone (LH) and follicular-stimulating hormone (FSH) levels in T. gondii-infected male mice. IOP effectively up-regulated testicular steroidogenic acute regulatory protein (StAR), P450scc and 17β-HSD expressions. IOP also significantly decreased the levels of malondialdehyde (MDA) and nitric oxide (NO), but increased the activities of antioxidant enzyme superoxide dismutase (SOD) and glutathione (GSH). Furthermore, IOP up-regulated the expressions of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) and NADPH quinoneoxidoreductase-1 (NQO-1), and suppressed the apoptosis of testicular cells by decreasing Bcl-2 associated x protein (Bax) and cleaved caspase-3 expressions. IOP further enhanced testicular phosphatidylinositol 3-kinase (PI3K), phospho-protein kinase B (p-AKT) and phospho-mammalian target of rapamycin (p-mTOR) expression levels. It demonstrates the beneficial effects of IOP on impaired reproductive function in T. gondii-infected male mice due to its anti-oxidative stress and anti-apoptosis via regulating Nrf2-PI3K/AKT signaling pathway.