Lentinan exerts synergistic apoptotic effects with paclitaxel in A549 cells via activating ROS-TXNIP-NLRP3 inflammasome

Nutritive profile, pharmaceutical potentials, and structural analysis of multifunctional bioactive fungal polysaccharides-A review

Asian nations have long used edible fungi as food and medicine. Polysaccharides are among the main building units of the cell walls of fungi. Fungal polysaccharides have been documented in the medicinal and industrial sectors as products with a vast array of various biological activities and applications such as antitumor, antioxidant, anticancer, immunomodulation, and antiviral activities, etc. The goal of this review is to give insights into the various biological activities of mushroom polysaccharides and their potential as a medicine for human health. The extraction, purity, and structural analysis of fungal polysaccharides were also reviewed in this work. Also, future prospective, and challenges for fungal polysaccharides in pharmaceutical applications can be found in this review. Overall, this review serves as a valuable resource in exploring the therapeutic potential and applications of fungal polysaccharides. By building upon the existing knowledge base and addressing critical research gaps, researchers can find new opportunities for utilizing fungal polysaccharides as valuable therapeutic agents and functional ingredients in pharmaceuticals, nutraceuticals, and biotechnology.

Traditional Chinese medicine polysaccharide in nano-drug delivery systems: Current progress and future perspectives

Traditional Chinese medicine polysaccharides (TCMPs) have gained increasing attention in the field of nanomedicine due to their diverse biological activities and favorable characteristics as drug carriers, including biocompatibility, biodegradability, safety, and ease of modification. TCMPs-based nano-drug delivery systems (NDDSs) offer several advantages, such as evasion of reticuloendothelial system (RES) phagocytosis, protection against biomolecule degradation, enhanced drug bioavailability, and potent therapeutic effects. Therefore, a comprehensive review of the latest developments in TCMPs-based NDDSs and their applications in disease therapy is of great significance. This review provides an overview of the structural characteristics and biological activities of TCMPs relevant to carrier design, the strategies employed for constructing TCMPs-based NDDSs, and the versatile role of TCMPs in these systems. Additionally, current challenges and future prospects of TCMPs in NDDSs are discussed, aiming to provide valuable insights for future research and clinical translation.

Doxorubicin-loaded zymosan nanoparticles: Synergistic cytotoxicity and modulation of apoptosis and Wnt/β-catenin signaling pathway in C26 colorectal cancer cells

Zymosan is a β-glucan isolated from Saccharomyces cerevisiae that could be employed for drug delivery. We synthesized zymosan nanoparticles and measured their structural and morphological properties using XRD, UV-Vis spectroscopy, TEM and AFM. The loading of doxorubicin (DOX) onto the nanoparticles was confirmed by FT-IR, and the DOX release was shown to be pH-dependent. The effect of these agents on C26 cell viability was evaluated by MTT tests and the expression of genes connected with the Wnt/β-catenin pathway and apoptosis were analyzed by RT-qPCR and Western blotting. Treatments were able to suppress the proliferation of C26 cells, and the zymosan nanocarriers loaded with DOX enhanced the anti-proliferative effect of DOX in a synergistic manner. Zymosan nanoparticles were able to suppress the expression of cyclin D1, VEGF, ZEB1, and Twist mRNAs. Treatment groups upregulated the expression of caspase-8, while reducing the Bax/Bcl-2 ratio, thus promoting apoptosis. In conclusion, zymosan nanoparticles as DOX nanocarriers could provide a more targeted drug delivery through pH-responsiveness, and showed synergistic cytotoxicity by modifying Wnt/β-catenin signaling and apoptosis.

Piperlongumine inhibits esophageal squamous cell carcinoma in vitro and in vivo by triggering NRF2/ROS/TXNIP/NLRP3-dependent pyroptosis

Pyroptosis, a type of programmed cell death, is characterized by cell swelling with bubbles, and the release of inflammatory cell cytokines. Piperlongumine (PL) is a natural bioactive product extracted from Piper longum L, which can effectively exert anti-tumor activities in cancer. However, the effects and the exact molecular mechanisms of PL in esophageal squamous cell carcinoma (ESCC) remain unclear. This research aimed to investigate the role and mechanism of PL on ESCC in vitro and in vivo. In vitro, the MTT results showed that the IC50 of PL in ESCC cells was 28.55 μM. Moreover, PL significantly suppressed malignant behavior by promoting pyroptosis of ESCC cells by inhibiting proliferation, migration, invasion, and colony formation of KYSE-30 cells, up-regulating expressions of ASC, Cleaved-caspase-1, NLRP3, and GSDMD, while inducing the generation of ROS. Further, NRF2 knockdown promoted TXNIP expression, while overexpression of NRF2 inhibited TXNIP expression. However, after PL treatment, this effect was reversed. In addition, PL significantly inhibited the malignant behavior of ESCC cells while the inhibitory effects were reversed by DMF (NRF2 activator) or NAC (ROS eliminator) treatment. Finally, PL markedly increased expressions of ASC, Cleaved-caspase-1, NLRP3, GSDMD, and the generation of ROS while the effects were reversed by TXNIP knockdown or RUS (TXNIP inhibitor) treatment. In vivo, the KYSE-30 xenograft model confirmed that PL inhibited the growth of ESCC transplanted tumors by promoting cell pyroptosis. In conclusion, the results suggested that PL inhibited the malignant behavior of ESCC cells in vitro and tumorigenesis of ESCC in vivo by inhibiting NRF2 and promoting ROS-TXNIP-NLRP3-mediated pyroptosis.

β-Glucan produced by Lentinus edodes suppresses breast cancer progression via the inhibition of macrophage M2 polarization by integrating autophagy and inflammatory signals

BACKGROUND

β-Glucan from Lentinus edodes (LNT), an edible mushroom, possesses strong anticancer activity. However, the therapeutic effects of LNT during the occurrence and progression of breast cancer and their underlying molecular mechanisms have not been elucidated.

METHODS

Mouse mammary tumor virus-polyoma middle tumor-antigen (MMTV-PyMT) transgenic mice were used as a breast cancer mouse model. Hematoxylin and eosin, immunohistochemical, and immunofluorescence staining were performed for histopathological analysis. Moreover, we developed an inflammatory cell model using tumor necrosis factor-α (TNF-α). Macrophage polarization was assessed using western blot analysis and immunofluorescence.

RESULTS

Orphan nuclear receptor 77 (Nur77) and sequestosome-1 (p62) were highly expressed and positively correlated with each other in breast cancer tissues. LNT significantly inhibited tumor growth, ameliorated inflammatory cell infiltration, and induced tumor cell apoptosis in PyMT transgenic mice. Moreover, LNT attenuated the ability of tumors to metastasize to lung tissue. Mechanistically, LNT treatment restrained macrophage polarization from M1 to M2 phenotype and promoted autophagic cell death by inhibiting Nur77 expression, AKT/mTOR signaling, and inflammatory signals in breast tumor cells. However, LNT did not exhibit a direct pro-autophagic effect on tumor cell death, except for its inhibitory effect on Nur77 expression. LNT-mediated autophagic tumor cell death depends on M1 macrophage polarization. In in vitro experiments, LNT inhibited the upregulation of p62, autophagy activation, and inflammatory signaling pathways in Nur77 cells.

CONCLUSION

LNT inhibited macrophage M2 polarization and subsequently blocked the AKT/mTOR and inflammatory signaling axes in breast cancer cells, thereby promoting autophagic tumor cell death. Thus, LNT may be a promising therapeutic strategy for breast cancer.

Chrysophanol exerts a protective effect against Aβ25-35-induced Alzheimer's disease model through regulating the ROS/TXNIP/NLRP3 pathway

BACKGROUND

The primary pathogenic factors of Alzheimer's disease (AD) have been identified as oxidative stress, inflammatory damage, and apoptosis. Chrysophanol (CHR) has a good neuroprotective effect on AD, however, the potential mechanism of CHR remains unclear.

PURPOSE

In this study, we focused on the ROS/TXNIP/NLRP3 pathway to determine whether CHR regulates oxidative stress and neuroinflammation.

METHODS

D-galactose and Aβ_25-35 combination were used to build an in vivo model of AD, and the Y-maze test was used to evaluate the learning and memory function of rats. Morphological changes of neurons in the rat hippocampus were observed using hematoxylin and eosin (HE) staining. AD cell model was established by Aβ_25-35 in PC12 cells. The DCFH-DA test identified reactive oxygen species (ROS). The apoptosis rate was determined using Hoechst33258 and flow cytometry. In addition, the levels of MDA, LDH, T-SOD, CAT, and GSH in serum, cell, and cell culture supernatant were detected by colorimetric method. The protein and mRNA expressions of the targets were detected by Western blot and RT-PCR. Finally, molecular docking was used to further verify the in vivo and in vitro experimental results.

RESULTS

CHR could significantly improve learning and memory impairment, reduce hippocampal neuron damage, and reduce ROS production and apoptosis in AD rats. CHR could improve the survival rate, and reduce the oxidative stress and apoptosis in the AD cell model. Moreover, CHR significantly decreased the levels of MDA and LDH, and increased the activities of T-SOD, CAT, and GSH in the AD model. Mechanically, CHR significantly reduced the protein and mRNA expression of TXNIP, NLRP3, Caspase-1, IL-1β, and IL-18, and increase TRX.

CONCLUSIONS

CHR exerts neuroprotective effects on the Aβ_25-35-induced AD model mainly by reducing oxidative stress and neuroinflammation, and the mechanism may be related to ROS/TXNIP/NLRP3 signaling pathway.

Lentinan: An unexplored novel biomaterial in drug and gene delivery applications

Recently, lentinan (LNT) has been utilized for its diversified potential in research with an extended role from nutritional or medicinal applications to a novel biomaterial. LNT is a biocompatible, multifunctional polysaccharide employed as a pharmaceutical additive in engineering customized drug or gene carriers with an improved safety profile. Its triple helical structure containing hydrogen bonding offers more extraordinary binding sites for the attachments of dectin-1 receptors and polynucleotide sequences (poly(dA)). Hence, the diseases expressing dectin-1 receptors can be specifically targeted through so-designed LNT-engineered drug carriers. Gene delivery using poly(dA)-s-LNT complexes and composites has exhibited greater targetability and specificity. The achievement of such gene applications is assessed through the pH and redox potential of the extracellular cell membrane. The steric hindrance-acquiring behavior of LNT shows promise as a system stabilizer in drug carrier engineering. LNT shows viscoelastic gelling behavior temperature-dependently and therefore needs to explore more to meet topical disease applications. The immunomodulatory and vaccine adjuvant properties of LNT help in mitigating viral infections too. This review highlights the new role of LNT as a novel biomaterial, particularly in drug delivery and gene delivery applications. In addition, its importance in achieving various biomedical applications is also discussed.

Exopolysaccharides of Fungal Origin: Properties and Pharmaceutical Applications

Fungal exopolysaccharides (EPSs) represent an important group of bioactive compounds secreted by fungi. These biopolymers can be utilized individually or in combination with different bioactive substances for a broad range of pharmaceutical field applications, due to their various biological activities, such as antioxidant, antimicrobial, anti-inflammatory, antiviral, anti-diabetic, and anticoagulant effects. The paper presents an up-to-date review of the main fungal polysaccharides (pullulan, schizophyllan, scleroglucan, botryosphaeran, lentinan, grifolan, and lasiodiplodan), highlighting their structures, producing strains, and useful properties in a double position, as controlled release (rate and selectively targeting) drug carriers, but mostly as active immunomodulating and antitumor compounds in cancer therapy.

The role of mitochondria-associated membranes mediated ROS on NLRP3 inflammasome in cardiovascular diseases

Reactive oxygen species (ROS) metabolism is essential for the homeostasis of cells. Appropriate production of ROS is an important signaling molecule, but excessive ROS production can damage cells. ROS and ROS-associated proteins can act as damage associated molecular pattern molecules (DAMPs) to activate the NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) inflammasome in cardiovascular diseases. Previous studies have shown that there are connected sites, termed mitochondria-associated membranes (MAMs), between mitochondria and the endoplasmic reticulum. In cardiovascular disease progression, MAMs play multiple roles, the most important of which is the ability to mediate ROS generation, which further activates the NLPR3 inflammasome, exacerbating the progression of disease. In this review, the following topics will be covered: 1. Molecular structures on MAMs that can mediate ROS generation; 2. Specific mechanisms of molecule-mediated ROS generation and the molecules' roles in cardiovascular disease, 3. The effects of MAMs-mediated ROS on the NLRP3 inflammasome in cardiovascular disease. The purpose of this review is to provide a basis for subsequent clinical treatment development.

Lentinan inhibits oxidative stress and alleviates LPS-induced inflammation and apoptosis of BMECs by activating the Nrf2 signaling pathway

Lentinan (LNT) has been reported to have a wide range of functions, including anti-inflammatory, antioxidant and anticancer properties. LNT may provide a protective effect in dairy cow mastitis. In this study, we investigated the effect of LNT on lipopolysaccharide (LPS)-induced injury of bovine mammary epithelial cells (BMECs) and the possible mechanism. First, we treated BMECs with different concentrations of LPS to study the effects of LPS on oxidative stress and inflammation in BMECs. Then, we examined the effects of LNT by dividing the cells into seven groups: the control group (CON), LPS treatment group (LPS), Acetyl-l-cysteine (NAC) pretreatment group (NAC + LPS), LNT pretreatment group (LNT + LPS), ML385 and LNT pretreatment group (ML385 + LNT + LPS), LNT treatment group (LNT) and NAC treatment group (NAC). The results showed that LPS-triggered intracellular ROS production and the downregulation of Nrf-2 and HO-1 in BMECs were blocked by LNT pretreatment. LNT inhibited the expression of inflammatory genes and proteins by inhibiting of NF-κB and MAPK. In addition, LNT attenuated LPS induced-apoptosis in BMECs. However, ML385 reversed the protective effect of LNT. Taken together, LNT can be used as a natural protective agent against LPS-triggered BMECs damage through its anti-inflammatory, antioxidant and antiapoptotic effects through modulation of the Nrf2 pathway.

Mechanisms of cancer cell death induction by paclitaxel: an updated review

Chemoresistance of cancer cells is a major problem in treating cancer. Knowledge of how cancer cells may die or resist cancer drugs is critical to providing certain strategies to overcome tumour resistance to treatment. Paclitaxel is known as a chemotherapy drug that can suppress the proliferation of cancer cells by inducing cell cycle arrest and induction of mitotic catastrophe. However, today, it is well known that paclitaxel can induce multiple kinds of cell death in cancers. Besides the induction of mitotic catastrophe that occurs during mitosis, paclitaxel has been shown to induce the expression of several pro-apoptosis mediators. It also can modulate the activity of anti-apoptosis mediators. However, certain cell-killing mechanisms such as senescence and autophagy can increase resistance to paclitaxel. This review focuses on the mechanisms of cell death, including apoptosis, mitotic catastrophe, senescence, autophagic cell death, pyroptosis, etc., following paclitaxel treatment. In addition, mechanisms of resistance to cell death due to exposure to paclitaxel and the use of combinations to overcome drug resistance will be discussed.

How Should the Worldwide Knowledge of Traditional Cancer Healing Be Integrated with Herbs and Mushrooms into Modern Molecular Pharmacology?

Traditional herbal medicine (THM) is a “core” from which modern medicine has evolved over time. Besides this, one third of people worldwide have no access to modern medicine and rely only on traditional medicine. To date, drugs of plant origin, or their derivates (paclitaxel, vinblastine, vincristine, vinorelbine, etoposide, camptothecin, topotecan, irinotecan, and omacetaxine), are very important in the therapy of malignancies and they are included in most chemotherapeutic regimes. To date, 391,000 plant and 14,000 mushroom species exist. Their medical and biochemical capabilities have not been studied in detail. In this review, we systematized the information about plants and mushrooms, as well as their active compounds with antitumor properties. Plants and mushrooms are divided based on the regions where they are used in ethnomedicine to treat malignancies. The majority of their active compounds with antineoplastic properties and mechanisms of action are described. Furthermore, on the basis of the available information, we divided them into two priority groups for research and for their potential of use in antitumor therapy. As there are many prerequisites and some examples how THM helps and strengthens modern medicine, finally, we discuss the positive points of THM and the management required to transform and integrate THM into the modern medicine practice.

Lentinan Protects against Nonalcoholic Fatty Liver Disease by Reducing Oxidative Stress and Apoptosis via the PPARα Pathway

Lentinan (LNT), a type of polysaccharide derived from Lentinus edodes, has manifested protective effects during liver injury and hepatocellular carcinoma, but little is known about its effects on nonalcoholic fatty liver disease (NAFLD). This study aimed to investigate whether LNT can affect the progression of NAFLD and the associated mechanisms. C57BL/6J mice were fed a normal chow diet or a high-fat diet (HFD) with or without LNT (6 mg/kg/d). AML12 cells were exposed to 200 μM palmitate acid (PA) with or without LNT (5 μg/mL). After 21 wk of the high-fat diet, LNT significantly decreased plasma triglyceride levels and liver lipid accumulation, reduced excessive reactive oxygen species production, and subsequently attenuated hepatic apoptosis in NAFLD mice. These effects were associated with increased PPARα levels, a decreased Bax/Bcl-2 ratio, and enhancement of the antioxidant defense system in vivo. Similar effects were also observed in cultured cells. More importantly, these protective effects of LNT on palmitate acid-treated AML12 cells were almost abolished by PPARα knockdown. In conclusion, this study demonstrates that LNT may ameliorate hepatic steatosis and decrease oxidative stress and apoptosis by activating the PPARα pathway and is a potential drug target for NAFLD.

Upregulation of miR-216a-5p by Lentinan Targeted Inhibition of JAK2/STAT3 Signaling Pathway to Reduce Lung Adenocarcinoma Cell Stemness, Promote Apoptosis, and Slow Down the Lung Adenocarcinoma Mechanisms

To investigate the effect of Lentinan (LNT) on lung adenocarcinoma (LUAD) cell stemness and its mechanism. In this study, we founded that LNT significantly reduce the cell proliferation, activity, migration, invasion, and stemness of LUAD cells, and promote their apoptosis compared with the control group in vitro. Moreover, LNT significantly inhibited the volume and weight of tumors of nude mice in vivo. At the same time, LNT can significantly up-regulate miR-216a-5p levels and reduce the protein expression of phospho-JAK2 (Y1007/1008) and phospho-STAT3 (Tyr705), thereby inhibiting the JAK2/STAT3 signaling pathway. Interfering with miR-216a-5p expression and activating the JAK2/STAT3 signaling pathway can significantly reverse LNT inhibitory effects on LUAD. Collectively, LNT can inhibit the JAK2/STAT3 signaling pathway by up-regulating miR-216a-5p, reducing stemness, and promoting LUAD cells apoptosis, then slow down LUAD occurrence and development, providing concepts and experimental foundation treating patients with LUAD.

Lentinan triggers oxidative stress-mediated anti-inflammatory responses in lung cancer cells

Inflammatory responses change several aspects of malignancies such as proliferation, survival, angiogenesis, and metastasis and lead to tumor progression. Lung cancer is the leading type of cancer worldwide and cancer-related inflammatory mediators challenge the successful treatments. Lentinan, a polysaccharide derived from Lentinula edodes, has shown anti-inflammatory characteristics in colitis and has been approved as an adjuvant therapy for cancer treatment. In the present study, we explored the mechanism underlying anti-inflammatory function of Lentinan in lung cancer cells. We showed that Lentinan reduced the inflammatory cytokines IL-6 and IL-1β in LPS-stimulated A549 cells at the concentrations much lower than the IC₅₀. Lentinan failed to alter the NLRP3 expression profile at transcriptional and translational levels. However, it showed a huge inhibition of caspase-1 activity. Lentinan downregulated the expression of IL-6 and IL-1β at the mRNA level. We also showed that Lentinan altered the oxidative status of the cells by increasing the intracellular ROS content and attenuating the activity of GPx4, the key player in the anti-oxidative defense system. Lentinan-induced ROS generation was associated with caspase-3 activation and induction of DNA breaks. This alteration was also associated with mitochondrial membrane depolarization shown by TMRE staining. Using recombinant caspase-1, we showed that Lentinan did not directly target caspase-1 but it led to caspase-1 inhibition. In conclusion, cytotoxicity and anti-inflammatory functions are separated by the dose of Lentinan. Lentinan increased the ROS and mitochondrial dysfunction in a level that is insufficient to induce cell death, but is sufficient to regulate the NLRP3 activation.

Oridonin improves the therapeutic effect of lentinan on lung cancer

Oridonin, a compound from Rabdosia rubescens, has been shown to exhibit a potent ability to improve the antitumor effects of lentinan (LNT). In the present study, the effects of oridonin, LNT, and the combination of these treatments were assessed on the normal human fetal lung fibroblast cell line MRC-5, as well as the non-small cell lung cancer cell line A549. Next, their effects on metastasis and survival in vivo were assessed in a mouse model of lung cancer. The effects of the treatments on the mRNA and protein expression levels of several regulatory factors in A549 cells and lung tissues were determined using reverse transcription-quantitative PCR and western blotting. The results showed that the viability of MRC-5 and A549 cells were not affected by 0-20 µg/ml oridonin; 0-300 µg/ml LNT did not affect the viability of MRC-5 cells, but 50-400 µg/ml LNT reduced the viability of A549 cells. Thus, 20 µg/ml oridonin and 100 or 300 µg/ml LNT were used in the subsequent experiments. Treatment with oridonin and LNT, alone or combined, had no effect on MRC-5 cell viability. Oridonin treatment had no effect on A549 cell viability; however, LNT suppressed A549 cell viability, and oridonin promoted the suppressive effects of LNT on A549 cells. In vivo analysis showed that oridonin alone had no effect on metastasis and survival, but LNT decreased metastasis and survival in mice. Oridonin augmented the effects of LNT against metastasis and further improved the survival rates of mice. In both A549 cells and lung tissues, LNT increased the mRNA and protein expression levels of caspase-3, caspase-8, caspase-9, Bax, p53, p21 and inhibitor of nuclear factor-κB (NF-κB)-α, and reduced the mRNA and protein expression levels of Bcl-2 and NF-κB. Oridonin augmented all the effects of LNT on expression of these proteins in the cells. Together, the results showed that oridonin enhanced the antitumor effects of LNT, and may thus serve as an adjuvant alongside LNT as a novel anticancer regimen for treatment of lung cancer.

Hedyotis diffusa plus Scutellaria barbata Suppress the Growth of Non-Small-Cell Lung Cancer via NLRP3/NF-κB/MAPK Signaling Pathways

Hedyotis diffusa (HD) plus Scutellaria barbata (SB) have been widely used in antitumor clinical prescribes as one of herb pairs in China. We investigated the effect of aqueous extract from Hedyotis diffusa plus Scutellaria barbata at the equal weight ratio (HDSB11) in inhibiting the growth of murine non-small-cell lung cancer cell (NSCLC) line LLC in vivo and in vitro in this study. Compared with other aqueous extracts, HDSB11 showed the lowest IC₅₀ in inhibiting cell proliferation at 0.43 mg/ml. Besides, HDSB11 effectively suppressed colony formation and induced cell apoptosis. The further assessment of HDSB11 on the murine Lewis-lung-carcinoma-bearing mouse model showed it significantly inhibited tumors' bioluminescence at the dose of 30 g crude drug/kg. Mechanistically, HDSB11 attenuated the expressions of NLRP3, procaspase-1, caspase-1, PRAP, Bcl-2, and cyclin D1 and downregulated the phosphorylation levels of NF-κB, ERK, JNK, and p38 MAPK. In conclusion, HDSB11 could alleviate cell proliferation and colony formation and induce apoptosis in vitro and tumor growth in vivo, partly via NF-κB and MAPK signaling pathways to suppress NLRP3 expression.

β-glucan from Lentinus edodes inhibits breast cancer progression via the Nur77/HIF-1α axis

Background: β-glucan from Lentinus edodes (LNT) is a plant-derived medicinal fungus possessing significant bioactivities on anti-tumor. Both hypoxia-induced factor-1α (HIF)-1α and Nur77 have been shown to be involved in the development of breast cancer. However, there is yet no proof of Nur77/HIF-1α involvement in the process of LNT-mediated tumor-inhibition effect.

Methods: Immunohistochemistry, immunofluorescence and Hematoxylin–Eosin staining were used to investigate tumor growth and metastasis in MMTV-PyMT transgenic mice. Proliferation and metastasis-associated molecules were determined by Western blotting and reverse transcription-quantitative PCR. Hypoxic cellular model was established under the exposure of CoCl₂. Small interference RNA was transfected using Lipofectamine reagent. The ubiquitin proteasome pathway was blunted by adding the proteasome inhibitor MG132.

Results: LNT inhibited the growth of breast tumors and the development of lung metastases from breast cancer, accompanied by a decreased expression of HIF-1α in the tumor tissues. In in vitro experiments, hypoxia induced the expression of HIF-1α and Nur77 in breast cancer cells, while LNT addition down-regulated HIF-1α expression in an oxygen-free environment, and this process was in a manner of Nur77 dependent. Mechanistically, LNT evoked the down-regulation of HIF-1α involved the Nur77-mediated ubiquitin proteasome pathway. A strong positive correlation between Nur77 and HIF-1α expression in human breast cancer specimens was also confirmed.

Conclusion: Therefore, LNT appears to inhibit the progression of breast cancer partly through the Nur77/HIF-1α signaling axis. The findings of the present study may provide a theoretical basis for targeting HIFs in the treatment of breast cancer.

Inhibition of thioredoxin-interacting protein and inflammasome assembly using verapamil mitigates diabetic retinopathy and pancreatic injury

It has been previously demonstrated by our group that genetic inhibition of thioredoxin-interacting-protein (TXNIP) preserved retinal neuronal function in chemically-induced retinopathy. Moreover, elevated intracellular levels of TXNIP and calcium ions play important roles in hyperglycemia-induced oxidative stress and inflammation. Current study aimed to appraise the potential therapeutic benefits of pharmacological inhibition of TXNIP using verapamil in diabetic retinopathy. Diabetic retinopathy was assessed in type-1 diabetes rat model induced by a single intravenous injection of streptozotocin (45 mg/kg), with or without daily treatment with verapamil (10 mg/kg, oral) for 4 months. Verapamil treatment commenced 48 h post-streptozotocin insult and continued for 16 weeks. Untreated diabetic rats exhibited higher expression of toll-like-receptor-4 (TLR4), TXNIP, nucleotide-binding domain-like receptor protein-3 (NLRP3), caspase-1, cytochrome-c, and ssDNA as assessed immunohistochemically in both retinal and pancreatic tissues 16 weeks post-diabetes induction. This was associated with a reduced thioredoxin reductase (Trx-R) activity, increased release of TNF-α and IL-1β into vitreous fluid along with retinal ganglion cell (RGC) loss, pancreatic islets shrinkage, and enhanced CD34 expression. The treatment with verapamil enhanced Trx-R activity, significantly inhibited TLR4 mediated NLRP3-inflammasome assembly with subsequent diminishing of inflammatory markers (TNF-α and IL-1β) release into the vitreous, suppression of pathological angiogenesis, and preservation of RGC count and pancreatic islets diameter. Current study showed that using the calcium channel blocker, verapamil, interferes with the pathogenesis of diabetic retinopathy and pancreatic islets damage at multiple levels mainly through the inhibition of TLR4, TXNIP and NLRP3-inflammasome, suggesting its promising role as an anti-diabetic and a neuroprotective agent.

ASK1/p38‑mediated NLRP3 inflammasome signaling pathway contributes to aberrant retinal angiogenesis in diabetic retinopathy

Diabetic retinopathy (DR) is the leading cause of blindness among the working-age population in several countries. Despite the available treatments, some patients are diagnosed at the late stages of the disease when treatment is more difficult. Hence, it is crucial that novel targets are identified in order to improve the clinical therapy of DR. In the present study, an animal model of DR and a cell model using primary human retinal microvascular endothelial cells exposed to high glucose were constructed to examine the association between apoptosis signal-regulating kinase 1 (ASK1)/p38 and NLR family pyrin domain containing 3 (NLRP3) in DR. The results revealed that DR induced inflammatory response and micro-vascular cell proliferation. NLRP3 contributed to DR-mediated inflammatory development and progression, which promoted the expression of inflammatory-related cytokines. In addition, NLRP3 promoted the tube formation of retinal microvascular endothelial cells and angiogenesis. Moreover, further research indicated that the NLRP3-mediated aberrant retinal angiogenesis in DR was regulated by ASK1 and p38. It was thus suggested that ASK1/p38 may be novel target for the treatment of DR.

Mushrooms and immunity

In the wide field of nutraceuticals, the effects of mushrooms on immunity, cancer and including autoimmunity have been proposed for centuries but in recent years a growing interest has led scientists to elucidate which specific compounds have bioactive properties and through which mechanisms. Glucans and specific proteins are responsible for most of the biological effects of mushrooms, particularly in terms of immunomodulatory and anti-tumor results. Proteins with bioactive effects include lectins, fungal immunomodulatory proteins (FIPs), ribosome inactivating proteins (RIPs), ribonucleases, laccases, among others. At the present status of knowledge, numerous studies have been performed on cell lines and murine models while only a few clinical trials have been conducted. As in most cases of dietary components, the multitude of variables implicated in the final effect and an inadequate standardization are expected to affect the observed differences, thus making the available evidence insufficient to justify the treatment of human diseases with mushrooms extracts. We will herein provide a comprehensive review and critically discussion the biochemical changes induced by different mushroom compounds as observed in in vitro studies, particularly on macrophages, dendritic cells, T cells, and NK cells, compared to in vivo and human studies. Additional effects are represented by lipids which constitute a minor part of mushrooms but may have a role in reducing serum cholesterol levels or phenols acting as antioxidant and reducing agents. Human studies provide a minority of available data, as well illustrated by a placebo-controlled study of athletes treated with β-glucan from Pleurotus ostreatus. Variables influencing study outcomes include different mushrooms strains, growing conditions, developmental stage, part of mushroom used, extraction method, and storage conditions. We foresee that future rigorous research will be needed to determine the potential of mushroom compounds for human health to reproduce the effects of some compounds such as lentinan which a metaanalysis demonstrated to increase the efficacy of chemotherapy in the treatment of lung cancer and in the improvement of the patients quality of life.

Antrodia camphorata polysaccharide resists 6-OHDA-induced dopaminergic neuronal damage by inhibiting ROS-NLRP3 activation

INTRODUCTION

Parkinson's disease (PD) is a common degenerative disease of the central nervous system (CNS). The main pathological change is the apoptosis of dopaminergic neurons in the substantia nigra pars compacta (SNPc), thereby leading to dopamine reduction in nigral striatum. 6-Hydroxydopamine (6-OHDA), a neurotoxic substance, mediates apoptosis of dopaminergic neurons and causes Parkinson-like symptoms in mice.

METHODS

Our team previously found that Antrodia camphorata polysaccharide (ACP) exerted a good behavioral improvement effect on the PD mouse model established by 6-OHDA; however, the mechanism remains unknown. Therefore, in this study, we focused on ROS-NLRP3 signal to investigate the mechanism of 6-OHDA-induced apoptosis of dopaminergic neurons MES23.5 and the protective effects of ACP on dopaminergic neurons.

RESULT

6-OHDA could further activate the expression of inflammasome NLRP3 by inducing ROS, thereby resulting in apoptosis of MES23.5 cells. ACP could inhibit the expression of ROS-NLRP3 induced by 6-OHDA, exerting a protective role in MES23.5 cells. Animal experiments also confirmed that ACP intervention could reduce the activation level of ROS-NLRP3 in the substantia nigra-striatum and improve the exercise capacity of PD mice.

CONCLUSION

Our study validated that 6-OHDA could induce apoptosis of dopaminergic neurons via ROS-NLRP3 activation. ACP could inhibit this signal and protect dopaminergic neurons, which might be promising in research of PD therapeutics.

Lentinan improved the efficacy of vaccine against Trichinella spiralis in an NLRP3 dependent manner

There is an urgent need for the development of new, improved vaccine adjuvants against T. spiralis infection. Polysaccharides are effective, safe, and biodegradable as adjuvant. In our study, we first observed the protective efficacy of lentinan as adjuvant against helminth T. spiralis infection. Recombinant T. spiralis Serpin (rTs-Serpin) immunoscreened from a cDNA library of T. spiralis, as a vaccine, protect host against Trichinella infection. The reduction rate of helminth burden of rTs-Serpin+lentinan–immunized mice was significantly increased compared with rTs-Serpin+FCA -immunized mice. rTs-Serpin+lentinan induced IgG1-dominant immune response and higher levels of IFN-γ and IL-4. rTs-Serpin+lentinan displayed a lower reduction rate of parasite burden in NLRP3^-/- mice than that in WT mice and lower level of IgG1 than that in WT mice. The level of IL-4, but not IFN-γ, from NLRP3^-/- mice immunized by rTs-Serpin+lentinan was significantly lower than that from WT mice, suggesting that NLRP3 is associated with rTs-Serpin+lentinan -triggering Th2 protective immunity against T. spiralis infection. In summary, we revealed that lentinan was a novel adjuvant against T. spiralis infection via NLRP3. NLRP3 therefore represents an important target for adjuvant discovery and the control of T. spiralis infection.

Trichinella spp., pathogenic agents of trichinellosis, is foodborne zoonotic nematodes cause huge economic burden to the livestock industry. The potential of new adjuvants for improving veterinary vaccines remains largely unexploited to trigger safe and long-lasting immunity in large animals, including livestock. Polysaccharides are effective, safe, and biodegradable as adjuvant. We first observed the protective efficacy of lentinan as a novel adjuvant against helminth T. spiralis infection. NLRP3 is associated with lentinan -triggering Th2 protective immunity against T. spiralis infection. NLRP3 therefore represents an important target for adjuvant discovery and the control of T. spiralis infection.

Immunomodulatory Effects of Diterpenes and Their Derivatives Through NLRP3 Inflammasome Pathway: A Review

Nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing protein (NLRP) inflammasomes are involved in the molecular pathogenesis of many diseases and disorders. Among NLRPs, the NLRP3 (in humans encoded by the NLRP3 gene) is expressed predominantly in macrophages as a component of the inflammasome and is associated with many diseases, including gout, type 2 diabetes, multiple sclerosis, atherosclerosis, and neurological diseases and disorders. Diterpenes containing repeated isoprenoid units in their structure are a member of some essential oils that possess diverse biological activities and are becoming a landmark in the field of drug discovery and development. This review sketches a current scenario of diterpenes or their derivatives acting through NLRPs, especially NLRP3-associated pathways with anti-inflammatory effects. For this, a literature survey on the subject has been undertaken using a number of known databases with specific keywords. Findings from the aforementioned databases suggest that diterpenes and their derivatives can exert anti-inflammatory effects via NLRPs-related pathways. Andrographolide, triptolide, kaurenoic acid, carnosic acid, oridonin, teuvincenone F, and some derivatives of tanshinone IIA and phorbol have been found to act through NLRP3 inflammasome pathways. In conclusion, diterpenes and their derivatives could be one of the promising compounds for the treatment of NLRP3-mediated inflammatory diseases and disorders.

TXNIP/TBP-2: A Master Regulator for Glucose Homeostasis

Identification of thioredoxin binding protein-2 (TBP-2), which is currently known as thioredoxin interacting protein (TXNIP), as an important binding partner for thioredoxin (TRX) revealed that an evolutionarily conserved reduction-oxidation (redox) signal complex plays an important role for pathophysiology. Due to the reducing activity of TRX, the TRX/TXNIP signal complex has been shown to be an important regulator for redox-related signal transduction in many types of cells in various species. In addition to its role in redox-dependent regulation, TXNIP has cellular functions that are performed in a redox-independent manner, which largely rely on their scaffolding function as an ancestral α-Arrestin family. Both the redox-dependent and -independent TXNIP functions serve as regulatory pathways in glucose metabolism. This review highlights the key advances in understanding TXNIP function as a master regulator for whole-body glucose homeostasis. The potential for therapeutic advantages of targeting TXNIP in diabetes and the future direction of the study are also discussed.

Effects of lentinan on NF-κB activity in the liver of burn rats with sepsis

Effects of lentinan on nuclear factor-κB (NF-κB) activity in liver of burn rats with sepsis were investigated. To mimic the clinical sepsis after burn, rats were subjected to 30% full-thickness scald injury, followed by intraperitoneal (i.p.) injection of lipopolysaccharide (LPS). Seventy-two adult rats were randomly divided into six groups: the normal control group (n=12); the burn sepsis group (n=12); the burn sepsis with positive drugs; the burn sepsis with low-dose lentinan treatment group (50.0 mg/kg, n=12); the burn sepsis with middle-dose lentinan treatment group (100.0 mg/kg, n=12) and the burn sepsis with high-dose lentinan treatment group (200.0 mg/kg, n=12). Expression of NF-κB in the liver was measured with western blot analysis. The morphology of liver was evaluated with hematoxylin and eosin staining. The expression of NF-κB significantly increased in the liver of burn rats with sepsis. Compared with the burn sepsis group, lentinan treatment obviously reduced the damage of hepatic cell morphology, and decreased the activity of NF-κB significantly in the medium and high concentrations of lentinan treatment groups (P<0.05). Most importantly, treatment with lentinan was able to reverse the increased concentration of IL-4, IL-6, IL-10 and TNF-α in plasma which was induced by LPS. Lentinan treatment can significantly decrease the expression of NF-κB in the liver of burn rats with sepsis.

Oxidative Damage in Sporadic Colorectal Cancer: Molecular Mapping of Base Excision Repair Glycosylases in Colorectal Cancer Patients

Oxidative stress with subsequent premutagenic oxidative DNA damage has been implicated in colorectal carcinogenesis. The repair of oxidative DNA damage is initiated by lesion-specific DNA glycosylases (hOGG1, NTH1, MUTYH). The direct evidence of the role of oxidative DNA damage and its repair is proven by hereditary syndromes (MUTYH-associated polyposis, NTHL1-associated tumor syndrome), where germline mutations cause loss-of-function in glycosylases of base excision repair, thus enabling the accumulation of oxidative DNA damage and leading to the adenoma-colorectal cancer transition. Unrepaired oxidative DNA damage often results in G:C>T:A mutations in tumor suppressor genes and proto-oncogenes and widespread occurrence of chromosomal copy-neutral loss of heterozygosity. However, the situation is more complicated in complex and heterogeneous disease, such as sporadic colorectal cancer. Here we summarized our current knowledge of the role of oxidative DNA damage and its repair on the onset, prognosis and treatment of sporadic colorectal cancer. Molecular and histological tumor heterogeneity was considered. Our study has also suggested an additional important source of oxidative DNA damage due to intestinal dysbiosis. The roles of base excision repair glycosylases (hOGG1, MUTYH) in tumor and adjacent mucosa tissues of colorectal cancer patients, particularly in the interplay with other factors (especially microenvironment), deserve further attention. Base excision repair characteristics determined in colorectal cancer tissues reflect, rather, a disease prognosis. Finally, we discuss the role of DNA repair in the treatment of colon cancer, since acquired or inherited defects in DNA repair pathways can be effectively used in therapy.

The NLRP3 inflammasome: a therapeutic target for inflammation-associated cancers

Introduction: Inflammasomes are large multimeric intracellular complexes that are capable of maturation and secretion of pro-inflammatory cytokines, IL-1β and IL-18, in response to danger signal molecules. As a member of the inflammasome family, the NLRP3 inflammasome has recently been under intense investigation revealing its possible role in several human diseases especially cancers.Areas covered: In this review, we will discuss the biology and mechanism of NLRP3 inflammasome activation, its role in specific types of tumors and the novel therapeutic modalities targeting this complex.Expert opinion: The NLRP3 inflammasome and its components including the adapter apoptosis-associated speck-like (ASC) protein and caspase-1 impose different and sometimes contrasting effects in tumorigenesis depending on various contexts. Considering the novel role of this complex in the initiation and progression of neoplasia, the NLRP3 inflammasome and its pathways provide desirable therapeutic targets for prevention, treatment, and prognosis of certain types of cancer. To date, several agents have been introduced for this purpose, some of which have shown promising results in the clinic.

Metabolic Syndrome, Brain Insulin Resistance, and Alzheimer's Disease: Thioredoxin Interacting Protein (TXNIP) and Inflammasome as Core Amplifiers

Empirical evidence indicates a strong association between insulin resistance and pathological alterations related to Alzheimer's disease (AD) in different cerebral regions. While cerebral insulin resistance is not essentially parallel with systemic metabolic derangements, type 2 diabetes mellitus (T2DM) has been established as a risk factor for AD. The circulating "toxic metabolites" emerging in metabolic syndrome may engage several biochemical pathways to promote oxidative stress and neuroinflammation leading to impair insulin function in the brain or "type 3 diabetes". Thioredoxin-interacting protein (TXNIP) as an intracellular amplifier of oxidative stress and inflammasome activation may presumably mediate central insulin resistance. Emerging data including those from our recent studies has demonstrated a sharp TXNIP upregulation in stroke, aging and AD and well underlining the significance of this hypothesis. With the main interest to illustrate TXNIP place in type 3 diabetes, the present review primarily briefs the potential mechanisms contributing to cerebral insulin resistance in a metabolically deranged environment. Then with a particular focus on plausible TXNIP functions to drive and associate with AD pathology, we present the most recent evidence supporting TXNIP as a promising therapeutic target in AD as an age-associated dementia.

Evaluation of Efficacy and Safety for Lentinan in the Control of the Malignant Pleural Effusions via Intrapleural Injection

BACKGROUND

Many studies have investigated the efficacy and safety of lentinan combined with cisplatin versus cisplatin alone for controlling malignant pleural effusion (MPE). This study is a meta-analysis of available evidence.

MATERIALS AND METHODS

Seventeen studies reporting lentinan combined with cisplatin versus cisplatin alone for controlling MPE were reviewed. Pooled odds ratios and hazard ratio with 95% confidence intervals were calculated using the fixed effects model of meta-analysis.

RESULTS

The overall response rate (ORR) of lentinan combined with cisplatin for controlling MPE was significantly higher than that of cisplatin alone (P < 0.001). In addition, lentinan combined with cisplatin showed a better benefit of quality of life (QOL) compared with cisplatin alone (P < 0.001). The main adverse effects (AEs) found in the control plan were hematological reactions, nausea/vomiting, chest pain and fever. However, the presence of lentinan did not have an extra influence on the incidence of AEs (P > 0.05).

CONCLUSIONS

Intrapleural injection of lentinan combined with cisplatin had a better benefit of ORR and QOL for controlling MPE, compared with cisplatin alone. Moreover, lentinan combined with cisplatin had a similar incidence of AEs with cisplatin alone.

Expression of a CARD Slows the Retinal Degeneration of a Geographic Atrophy Mouse Model

Age-related macular degeneration (AMD) has been linked to oxidative damage and para-inflammation, an activation of inflammasome signaling in the retinal pigment epithelium (RPE) and the underlying choriocapillaris. Herein, we tested the efficacy of a gene-delivered caspase-1 inhibitor in controlling the retinal degeneration observed in two models of RPE-choroid oxidative damage. In an acute model of oxidative stress (NaIO3 injection), eyes pre-treated with the sGFP-TatCARD (trans-activator of transcription; caspase activation and recruitment domain) vector demonstrated a recovery of retinal function and partial protection of RPE structure 1 month after damage, in contrast with control-treated eyes. In a model of chronic oxidative stress (RPE-specific deletion of Sod2), eyes treated with the sGFP-TatCARD vector after the onset of degeneration had a significantly slower decline in retinal function when compared to control-treated eyes. Earlier treatment of this model with the same adeno-associated virus (AAV) vector resulted in a greater protection of RPE function in eyes treated with the TatCARD when compared to control-treated eyes. Our results demonstrate that intravitreal delivery of sGFP-TatCARD reduces inflammation and can protect the retina from both acute and sustained oxidative damage within the RPE and choroid. Therefore, gene therapy with a cell-penetrating inflammasome inhibitor such as CARD may stem the progression of AMD.

Chemotherapeutic Agent Paclitaxel Mediates Priming of NLRP3 Inflammasome Activation

Paclitaxel is a chemotherapeutic drug commonly used to treat different types of cancer. In addition to its antitumor effect, paclitaxel is also known to promote Toll-like receptor (TLR) 4-dependent inflammatory responses, which may lower its chemotherapeutic efficacy. However, it remains unclear whether paclitaxel is able to affect inflammasome signaling in myeloid or cancer cells. Therefore, we examined the potential effect of paclitaxel on the activation of an inflammasome complex by examining caspase-1 activation and interleukin (IL)-1β secretion in bone marrow-derived macrophages (BMDMs). The results showed that treatment with paclitaxel alone or following LPS priming failed to trigger the secretion of active caspase-1 and IL-1β from BMDMs. However, paclitaxel could induce robust activation of caspase-1 in BMDMs in the presence of NLRP3 inflammasome-activating signal 2, such as ATP or nigericin. This paclitaxel/ATP-mediated inflammasome activation was completely abrogated in Nlrp3-deficient macrophages. Mechanistically, paclitaxel treatment induced robust activation of the TLR4 signaling cascade, including phosphorylation of IκB and JNK and upregulation of proinflammatory cytokine mRNA levels in a TLR4-dependent manner. In contrast, paclitaxel treatment alone did not induce mitochondrial damages such as the loss of the mitochondrial membrane potential and production of mitochondrial ROS. These findings suggest that paclitaxel can drive the priming of signal-mediated events for NLRP3 activation but not a second signal-triggered phenomenon such as mitochondrial damage. This suggestion was supported by the observations that paclitaxel treatment caused robust IL-1β production in macrophages in the presence of cell-free medium derived from growth of injured cells and also in the spleen of mice. Collectively, our data strongly indicate that paclitaxel is able to facilitate the activation of NLRP3 inflammasome signaling in a certain physiological environment.

Paclitaxel Enhances the Innate Immunity by Promoting NLRP3 Inflammasome Activation in Macrophages

Microtubules play critical roles in regulating the activation of NLRP3 inflammasome and microtubule-destabilizing agents such as colchicine have been shown to suppress the activation of this inflammasome. However, it remains largely unknown whether paclitaxel, a microtubule-stabilizing agent being used in cancer therapy, has any influences on NLRP3 inflammasome activation. Here we showed that paclitaxel pre-treatment greatly enhanced ATP- or nigericin-induced NLRP3 inflammasome activation as indicated by increased release of cleaved caspase-1 and mature IL-1β, enhanced formation of ASC speck, and increased gasdermin D cleavage and pyroptosis. Paclitaxel time- and dose-dependently induced α-tubulin acetylation in LPS-primed murine and human macrophages and further increased ATP- or nigericin-induced α-tubulin acetylation. Such increased α-tubulin acetylation was significantly suppressed either by resveratrol or NAD⁺ (coenzyme required for deacetylase activity of SIRT2), or by genetic knockdown of MEC-17 (gene encoding α-tubulin acetyltransferase 1). Concurrently, the paclitaxel-mediated enhancement of NLRP3 inflammasome activation was significantly suppressed by resveratrol, NAD⁺, or MEC-17 knockdown, indicating the involvement of paclitaxel-induced α-tubulin acetylation in the augmentation of NLRP3 inflammasome activation. Similar to paclitaxel, epothilone B that is another microtubule-stabilizing agent also induced α-tubulin acetylation and increased NLRP3 inflammasome activation in macrophages in response to ATP treatment. Consistent with the in vitro results, intraperitoneal administration of paclitaxel significantly increased serum IL-1β levels, reduced bacterial burden, dampened infiltration of inflammatory cells in the liver, and improved animal survival in a mouse model of bacterial infection. Collectively, our data indicate that paclitaxel potentiated NLRP3 inflammasome activation by inducing α-tubulin acetylation and thereby conferred enhanced antibacterial innate responses, suggesting its potential application against pathogenic infections beyond its use as a chemotherapeutic agent.

Reactive oxygen species in colorectal cancer: The therapeutic impact and its potential roles in tumor progression via perturbation of cellular and physiological dysregulated pathways

Reactive oxygen species (ROS) are produced by mitochondria during metabolism. In physiological states, the production of ROS and their elimination by antioxidants are kept in balance. However, in pathological states, elevated levels of ROS interact with susceptible cellular target compounds including lipids, proteins, and DNA and deregulate oncogenic signaling pathways that are involved in colorectal cancer (CRC) carcinogenesis. Although antioxidant compounds have been successfully used in the treatment of CRC as prevention approaches, they have also been shown in some cases to promote disease progression. In this review, we focus on the role of ROS in gastrointestinal homeostasis, CRC progression, diagnosis, and therapy with particular emphasis on ROS-stimulated pathways.

Lentinan as an immunotherapeutic for treating lung cancer: a review of 12 years clinical studies in China

PURPOSE

Lentinan is a polysaccharide extracted from Shiitake mushrooms that have been used to improve general health for thousands of years in Asia. Lentinan injection is a clinically approved drug in several countries in Asia. The purpose of this study is to review the structure, preclinical and clinical studies, and molecular mechanisms of lentinan. Most importantly, the clinical effectiveness of lentinan as an adjuvant therapeutic drug in treating patients with lung cancer in China during the past 12 years is analyzed statistically.

METHODS

We carried out literature search of randomized controlled trials (RCTs) published from 2004 to 2016 based on CNKI (China National Knowledge Infrastructure), VIP (Chongqing VIP Chinese Scientific Journals Database) and Wanfang database, and 38 eligible RCTs of lentinan-associated lung cancer treatment were identified, containing 3,117 patients.

RESULTS

The structure and function relationship and underlying molecular mechanism of lentinan as an immunostimulant has been summarized. The mean value of overall response rate in treating lung cancer was increased from 43.3% of chemotherapy alone to 56.9% of lentinan plus chemotherapy [p < 0.001, 95% confidence interval (CI) 0.102-0.170]. Compared with chemotherapy alone, lentinan plus chemotherapy showed more efficacy in treating lung cancer (pooled RR 0.79, 95% CI 0.74-0.85) and no statistical heterogeneity was found among studies (I² = 11%).

CONCLUSION

Clinical data presented in the past 12 years shows that lentinan is effective not only in improving quality of life, but also in promoting the efficacy of chemotherapy during lung cancer treatment.

Linarin prevents LPS‑induced acute lung injury by suppressing oxidative stress and inflammation via inhibition of TXNIP/NLRP3 and NF‑κB pathways

Acute lung injury (ALI) is an important cause of morbidity and mortality for critically ill patients, and linarin (LR) may be a potential treatment for ALI as it reportedly has antioxidant, anti-inflammatory and apoptotic-regulating activity. In the present study, the authors report that saline and LR (12.5, 25 and 50 mg/kg) were applied to male C57BL/6 mice via gavage. Then, mice were intratracheally injected with either saline or lipopolysaccharide (LPS). LR-pretreatment attenuated LPS-induced ALI and platelet activation and reduced CD41 expression levels and neutrophil platelet aggregates. Additionally, LPS-triggered pulmonary myeloperoxidase activity and neutrophil infiltration in lung tissues, and this was eliminated by LR dose-dependently. Furthermore, LPS-induced oxidative stress and pro-inflammatory cytokine release were downregulated by LR by inhibiting thioredoxin-interacting protein and nuclear factor-κB signaling pathways, including their downstream and upstream signals, such as xanthine oxidase, NLR family WHAT, pyrin domain-containing 3 (NLRP3), apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain (ASC), caspase-1, IκB kinase-α (IKK-α) and IκBα. Moreover, in LPS-induced mice, the mitogen-activated protein kinase pathway was inactivated by LR. In vitro, LR reduced LPS-induced inflammation and oxidative stress, which was linked to reduction of ROS. In conclusion, LR pretreatment may be protective against LPS-induced ALI.

Enhanced vulnerability to oxidative stress and induction of inflammatory gene expression in 3-phosphoglycerate dehydrogenase-deficient fibroblasts

l‐Serine (l‐Ser) is a necessary precursor for the synthesis of proteins, lipids, glycine, cysteine, d‐serine, and tetrahydrofolate metabolites. Low l‐Ser availability activates stress responses and cell death; however, the underlying molecular mechanisms remain unclear. l‐Ser is synthesized de novo from 3‐phosphoglycerate with 3‐phosphoglycerate dehydrogenase (Phgdh) catalyzing the first reaction step. Here, we show that l‐Ser depletion raises intracellular H₂O₂ levels and enhances vulnerability to oxidative stress in Phgdh‐deficient mouse embryonic fibroblasts. These changes were associated with reduced total glutathione levels. Moreover, levels of the inflammatory markers thioredoxin‐interacting protein and prostaglandin‐endoperoxide synthase 2 were upregulated under l‐Ser‐depleted conditions; this was suppressed by the addition of N‐acetyl‐l‐cysteine. Thus, intracellular l‐Ser deficiency triggers an inflammatory response via increased oxidative stress, and de novo l‐Ser synthesis suppresses oxidative stress damage and inflammation when the external l‐Ser supply is restricted.

Activation of NLRP3 inflammasome in peripheral nerve contributes to paclitaxel-induced neuropathic pain

Background

Paclitaxel is commonly used as a cancer chemotherapy drug that frequently causes peripheral neuropathic pain. Inflammasome is a multiprotein complex consisting of Nod-like receptor proteins (NLRPs), apoptosis-associated speck-like protein, and caspase-1, which functions to switch on the inflammatory process and the release of interleukin-1β. Growing evidences have supported that peripheral interleukin-1β is critical in enhancing paclitaxel-induced neuropathic pain. However, whether activation of NLRP3 inflammasome in peripheral nerve contributes to paclitaxel-induced neuropathic pain is still unclear.

Results

Paclitaxel induced mechanical allodynia of rats from day 3 and worsened gradually till 3 weeks after injection. Paclitaxel resulted in expression of NLRP3 and activated fragments of caspase-1 and interleukin-1β in L4-6 dorsal root ganglia and sciatic nerve three weeks after injection, indicating activation of NLRP3 inflammasome. The expression of NLRP3 was located in CD68-labeled macrophages infiltrating in L4-6 dorsal root ganglia and sciatic nerve, and paclitaxel increased the expression of NLRP3 in macrophage. Moreover, the paclitaxel elicited mitochondria damage, which became swollen and enlarged in macrophages and axons of sciatic nerve three weeks after injection. In vitro, paclitaxel increased the number of damaged mitochondria and mitochondrial reactive oxygen species production in the rat alveolar macrophage cell line NR8383. The administration of a non-specific reactive oxygen species scavenger, phenyl-N-tert-butylnitrone, markedly alleviated mechanical allodynia and inhibited the activation of NLRP3 inflammasome in L4-6 dorsal root ganglia and sciatic nerve of the paclitaxel-induced neuropathic pain model.

Conclusions

Paclitaxel induced mechanical allodynia and activation of NLRP3 inflammasome in infiltrated macrophages of L4-6 dorsal root ganglia and sciatic nerve. Paclitaxel elicited mitochondria damage and reactive oxygen species production may result in activation of NLRP3 inflammasome in peripheral nerve, which contributes to paclitaxel-induced neuropathic pain.

Thioredoxin-Interacting Protein (TXNIP) in Cerebrovascular and Neurodegenerative Diseases: Regulation and Implication

Neurological diseases, including acute attacks (e.g., ischemic stroke) and chronic neurodegenerative diseases (e.g., Alzheimer's disease), have always been one of the leading cause of morbidity and mortality worldwide. These debilitating diseases represent an enormous disease burden, not only in terms of health suffering but also in economic costs. Although the clinical presentations differ for these diseases, a growing body of evidence suggests that oxidative stress and inflammatory responses in brain tissue significantly contribute to their pathology. However, therapies attempting to prevent oxidative damage or inhibiting inflammation have shown little success. Identification and targeting endogenous "upstream" mediators that normalize such processes will lead to improve therapeutic strategy of these diseases. Thioredoxin-interacting protein (TXNIP) is an endogenous inhibitor of the thioredoxin (TRX) system, a major cellular thiol-reducing and antioxidant system. TXNIP regulating redox/glucose-induced stress and inflammation, now is known to get upregulated in stroke and other brain diseases, and represents a promising therapeutic target. In particular, there is growing evidence that glucose strongly induces TXNIP in multiple cell types, suggesting possible physiological roles of TXNIP in glucose metabolism. Recently, a significant body of literature has supported an essential role of TXNIP in the activation of the NOD-like receptor protein (NLRP3)-inflammasome, a well-established multi-molecular protein complex and a pivotal mediator of sterile inflammation. Accordingly, TXNIP has been postulated to reside centrally in detecting cellular damage and mediating inflammatory responses to tissue injury. The majority of recent studies have shown that pharmacological inhibition or genetic deletion of TXNIP is neuroprotective and able to reduce detrimental aspects of pathology following cerebrovascular and neurodegenerative diseases. Conspicuously, the mainstream of the emerging evidences is highlighting TXNIP link to damaging signals in endothelial cells. Thereby, here, we keep the trend to present the accumulative data on CNS diseases dealing with vascular integrity. This review aims to summarize evidence supporting the significant contribution of regulatory mechanisms of TXNIP with the development of brain diseases, explore pharmacological strategies of targeting TXNIP, and outline obstacles to be considered for efficient clinical translation.

Physiological roles of ASK family members in innate immunity and their involvement in pathogenesis of immune diseases

Cells are always exposed to various types of stress, including physical, chemical, and biological stresses, and are required to sense immediately and respond appropriately to these stresses. The apoptosis signal-regulating kinase (ASK) family members are stress-responsive kinases, which are activated by not only physicochemical stresses, such as oxidative stress, osmotic pressure, calcium overload, and anti-cancer drugs, but also biological stresses, such as inflammatory cytokines and pathogen infection. Recently, we found that ASK1, a member of ASK family, is activated by bacterial components, such as lipopolysaccharide, in a reactive oxygen species (ROS)-dependent manner, demonstrating that ASK1 is required for the innate immune response and plays a critical role in the regulation of innate immune signaling. Moreover, our findings indicate that ROS are common mediators in physicochemical stress signaling, including redox signaling, and biological stress signaling, including innate immune signaling. This review especially focuses on the roles of ASK family in innate immunity and provides recent progress in our knowledge on activation mechanisms and physiological functions of ASK family kinases in innate immune responses.

The β-glucan from Lentinus edodes suppresses cell proliferation and promotes apoptosis in estrogen receptor positive breast cancers

Breast cancer is now the most common cancer in worldwide women, and novel interventions are needed to overcome the resistance occurring in the estrogen-targeted endocrine therapy. Herein, we demonstrate that the β-glucan from Lentinus edodes (LNT) exhibited a profound inhibition ratio of ∼53% against estrogen receptor positive (ER+) MCF-7 tumor growth in nude mice similar to the positive control of cisplatin. Immunohistochemistry images showed that LNT evidently suppressed cell proliferation and promoted apoptosis in MCF-7 tumor tissues. The Western blotting analysis indicated that LNT up-regulated the tumor suppressor p53, phosphorylated extracellular signal-regulated kinase1/2 (p-ERK1/2), cleaved-Caspase 3 and poly [ADP (ribose)] polymerase 1 (PARP 1) protein levels, and reduced the expression of mouse double minute 2 (MDM2), telomerase reverse transcriptase (TERT), nuclear factor-kappa B (NF-κB) p65, B-cell lymphoma-2 (Bcl-2), estrogen receptor α (ERα), etc. in tumor tissues. Moreover, LNT significantly suppressed phosphatidylinositol 3-kinase (PI3K), phosphorylated protein kinase B (p-Akt) and mammalian target of rapamycin (mTOR) protein levels. It was thus proposed that LNT inhibited MCF-7 tumor growth through suppressing cell proliferation and enhancing apoptosis possibly via multiple pathways such as PI3K/Akt/mTOR, NF-κB-, ERK-, ERα-, caspase- and p53-dependent pathways. Interestingly, the cell viability assay, siRNA transfection, Western blotting and flow cytometric analysis suggested that LNT targeted p53/ERα to only suppress cell proliferation via cell cycle arrest at G2/M phase without apoptosis in vitro. The big difference between in vivo and in vitro data suggested that the immune responses triggered by the polysaccharide should mainly contribute to the apoptotic effect in vivo. Overall, this work provides a novel strategy to treat ER+ breast cancers by using a naturally occurring β-glucan from mushrooms.

Efficacy of biological response modifier lentinan with chemotherapy for advanced cancer: a meta-analysis

Lentinan is a common biological response modifier. This study was sought to evaluate the efficacy of adjuvant lentinan combined with chemotherapy for advanced cancer. A meta-analysis of published prospective controlled trials investigating the effects of lentinan for kinds of advanced cancer was performed. Sensitivity analysis, inverted funnel plots, and trial sequence analysis were conducted to explore the reliability and stability of results. Seventeen clinical studies were identified containing 1423 patients. Twelve trials included gastrointestinal cancer (GIC), three trials included lung cancer (LC), and two trials included the two cancers. There was a increase in survival rate in 1 year (risk ratios [RR], 1.46, P = 0.001) and overall response rate including both complete and partial response (RR, 1.28, P = 0.005). There was also a reduction in progressive disease (RR, 0.57, P = 0.0005), nonsevere adverse events (RR, 0.88, P = 0.004), and severe adverse events (RR, 0.73, P = 0.007). Similar results were shown in the two subgroups of GIC and LC. Limited trials reported the data of median overall survival and time to treatment failure, and the data were insufficient for quantitative analysis, and no significant difference were found in 2-year survival rate. Adjuvant lentinan used with chemotherapy achieved improvements in 1-year survival rate, response rate, and adverse events in advanced cancer. The effect seemed to be similar irrespective of cancer type. However, its sustained efficacy on survival was still unclear.

The Role of Reactive Oxygen Species and Autophagy in Periodontitis and Their Potential Linkage

Periodontitis is a chronic inflammatory disease that causes damage to periodontal tissues, which include the gingiva, periodontal ligament, and alveolar bone. The major cause of periodontal tissue destruction is an inappropriate host response to microorganisms and their products. Specifically, a homeostatic imbalance between reactive oxygen species (ROS) and antioxidant defense systems has been implicated in the pathogenesis of periodontitis. Elevated levels of ROS acting as intracellular signal transducers result in autophagy, which plays a dual role in periodontitis by promoting cell death or blocking apoptosis in infected cells. Autophagy can also regulate ROS generation and scavenging. Investigations are ongoing to elucidate the crosstalk mechanisms between ROS and autophagy. Here, we review the physiological and pathological roles of ROS and autophagy in periodontal tissues. The redox-sensitive pathways related to autophagy, such as mTORC1, Beclin 1, and the Atg12-Atg5 complex, are explored in depth to provide a comprehensive overview of the crosstalk between ROS and autophagy. Based on the current evidence, we suggest that a potential linkage between ROS and autophagy is involved in the pathogenesis of periodontitis.

Redox Imbalance in the Development of Colorectal Cancer

Redox imbalance is resulted from the destruction of balance between oxidants and antioxidants. The dominant oxidants are reactive oxygen species (ROS), which are involved in multiple cellular processes by physiologically transporting signal as a second messenger or pathologically oxidizing DNA, lipids, and proteins. Generally speaking, low concentration of ROS is indispensable for cell survival and proliferation. However, high concentration of ROS is cytotoxic. Additionally, ROS are now known to induce the oxidative modification of macromolecules especially proteins. The redox modification of proteins is involved in numerous biological processes related to diseases including CRC. Herein, we attempt to afford an overview that highlights the crosstalk between redox imbalance and CRC.

Lentinan from shiitake selectively attenuates AIM2 and non-canonical inflammasome activation while inducing pro-inflammatory cytokine production

Lentinan extracted from shiitake (Lentinula edodes) is a β-glucan that has been reported as an intravenous anti-tumor polysaccharide via enhancement of the host immune system. In this study, we determined the effect of lentinan on inflammasome activation, a multi-protein platform, in myeloid cells. Mouse bone marrow-derived macrophages were treated with lentinan with/without inflammasome triggers, and maturation of interleukin (IL)-1β, IL-18, or caspase-1 was measured as a readout of inflammasome activation. As a result, lentinan selectively inhibited absent in melanoma 2 (AIM2) inflammasome activation. In addition, lentinan up-regulated pro-inflammatory cytokines and induced expression of inflammasome-related genes through toll-like receptor 4 signaling. Furthermore, we assessed the effect of lentinan on mice treated with Listeria monocytogenes or lipopolysaccharide as an AIM2 or non-canonical inflammasome-mediated model. Lentinan attenuated IL-1β secretion resulting from Listeria-mediated AIM2 inflammasome activation and reduced endotoxin lethality via inhibition of non-canonical inflammasome activation. Thus, lentinan is suggested as an anti-AIM2 and anti-non-canonical inflammasome candidate despite its up-regulation of cytokine expression.