Gallic Acid-g-Chitosan Modulates Inflammatory Responses in LPS-Stimulated RAW264.7 Cells Via NF-κB, AP-1, and MAPK Pathways

Dietary Supplementation with Sea Bass (Lateolabrax maculatus) Ameliorates Ulcerative Colitis and Inflammation in Macrophages through Inhibiting Toll-Like Receptor 4-Linked Pathways

Sea bass (Lateolabrax maculatus) is a kind of food material commonly consumed in daily life. In traditional Chinese medicinal books, it has been indicated that sea bass can be applied for managing many inflammation-associated conditions. However, the studies on the pharmacological mechanisms of inflammation of sea bass remain scarce. Hence, this study aims to investigate the molecular mechanisms of the anti-inflammatory activity of sea bass. Anti-inflammatory activities of sea bass were assessed using dextran sulfate sodium (DSS)-induced colitis in a mice model and lipopolysaccharide (LPS)-activated macrophages model. Low body weight and short colon length were observed in DSS-fed mice that were significantly recovered upon sea bass treatments. Moreover, the colon histopathology score showed that sea bass-treated mice had decreased crypt damage, focal inflammation infiltration and the extent of inflammation, suggesting that treatment with sea bass could attenuate intestinal inflammation. In addition, the in-vitro study conjointly indicated that sea bass could suppress the inflammatory mediators in LPS-activated macrophage by inhibiting the TLR4-linked pathway. The present findings demonstrated that sea bass has an inhibitory effect on TLR4 signaling; thus, it could be a promising candidate for treating inflammation-associated conditions. A further justification for the clinical application of sea bass in treating inflammation-associated conditions is necessary.

Pharmacological effects of gallic acid in health and diseases: A mechanistic review

OBJECTIVES

Gallic acid is a natural phenolic compound found in several fruits and medicinal plants. It is reported to have several health-promoting effects. This review aims to summarize the pharmacological and biological activities of gallic acid in vitro and animal models to depict the pharmacological status of this compound for future studies.

MATERIALS AND METHODS

All relevant papers in the English language were collected up to June 2018. The keywords of gallic acid, antioxidant, anticancer, antimicrobial, gastrointestinal-, cardiovascular-, metabolic-, neuropsychological-, and miscellaneous- diseases were searched in Google Scholar, PubMed, and Scopus.

RESULTS

Several beneficial effects are reported for gallic acid, including antioxidant, anti-inflammatory, and antineoplastic properties. This compound has been reported to have therapeutic activities in gastrointestinal, neuropsychological, metabolic, and cardiovascular disorders.

CONCLUSION

Current evidence confirms the pharmacological and therapeutic interventions of gallic acid in multiple health complications; however, available data are limited to just cellular and animal studies. Future investigations are essential to further define the safety and therapeutic efficacy of gallic acid in humans.

A novel Rhein derivative: Activation of Rac1/NADPH pathway enhances sensitivity of nasopharyngeal carcinoma cells to radiotherapy

Radiation resistance and recurrent have become the major factors resulting in poor prognosis in the clinical treatment of patients with nasopharyngeal carcinoma (NPC). New strategies to enhance the efficacy of radiotherapy have been focused on the development of radiosensitizers and searching for directly targets that modulated tumor radiosensitivity. A novel potential radiosensitizer 1,8-Dihydroxy -3-(2'-(4″-methylpiperazin-1″-yl) ethyl-9,10-anthraquinone -3-carboxylate (RP-4) was designed and synthesized based on molecular docking technology, which was expected to regulate the radiosensitivity of tumor cells through targeting Rac1. In order to assess the radiosensitization activity of RP-4 on NPC cells, the highly differentiated CNE1 and poorly differentiated CNE2 cells NPC lines were employed. According to the results, RP-4 showed higher binding affinity toward the interaction with Rac1 than lead compounds. We found that RP-4 could inhibit cell viability and proliferation in CNE1 and CNE2 cells and significantly induced apoptosis after non-toxic concentration of RP-4 combined with 2Gy irradiation. RP-4 could effectively modulated the radiosensitivity both CNE1 cells and CNE2 cells through activating Rac1/NADPH signaling pathway and its downstream JNK/AP-1 pathway. What's more, Rac1/NADPH signaling pathway were significantly activated in Rac1-overexpressed CNE1 and CNE2 cells after treated with RP-4. Taken together, Rac1 and its downstream pathway may probably be the direct targets of RP-4 in regulating radiosensitivity of NPC cells, our finding provided a novel strategy for the development of therapeutic agents in response to tumorous radiation resistance.

Chitosan/hyaluronic acid/plasmid-DNA nanoparticles encoding interleukin-1 receptor antagonist attenuate inflammation in synoviocytes induced by interleukin-1 beta

Synovial inflammation mainly resulting from interleukin-1 beta (IL-1β) plays a crucial role in the early and late stage of osteoarthritis. Recent progress in therapeutic gene delivery systems has led to promising strategies for local sustained target gene expression. The aim of this study was to design a nanoparticle made of chitosan (CS)/hyaluronic acid (HA)/plasmid-DNA (pDNA) encoding IL-1 receptor antagonist gene (pIL-1Ra) and furtherly use it to transfect the primary synoviocytes, and then investigate whether CS/HA/pIL-1Ra nanoparticles could make the synoviocytes overexpress functional IL-1Ra to attenuate inflammation induced by IL-1β. In this study, CS was modified with HA to generate CS/HA nanoparticles and then combined with pIL-1Ra to form CS/HA/pIL-1Ra nanoparticles. The physicochemical characteristics results showed that CS/HA nanoparticles exhibited an appropriate particle size (144.9 ± 2.8 nm) and positive zeta potential ( + 28 mV). The gel retardation assay revealed that pDNA was effectively protected and released in a sustained manner more than 15 days. Cytotoxicity results showed that CS/HA/pIL-1Ra nanoparticles had a safe range (0-80 μg/ml) for the application to synoviocytes. RT-qPCR and western blot analysis demonstrated that CS/HA/pIL-1Ra nanoparticles were able to increase IL-1Ra expression in primary synoviocytes, and reduce the mRNA and protein levels of matrix metalloproteinase-3 (MMP-3), matrix metalloproteinase-13 (MMP-13), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in IL-1β-induced synoviocytes. Our findings indicated that CS/HA/pIL-1Ra nanoparticles efficiently transfected synoviocytes and attenuated synovitis induced by IL-1β, which will provide a potential strategy for OA synovitis.

Casein glycomacropeptide hydrolysates inhibit PGE2 production and COX2 expression in LPS-stimulated RAW 264.7 macrophage cells via Akt mediated NF-κB and MAPK pathways

A casein glycomacropeptide hydrolysate (GMPH) was found to possess inhibitory activity against lipopolysaccharide (LPS)-induced inflammatory response in our previous study. In the current study, the inhibitory effect and the underlying molecular mechanism of GMPH on inflammatory response in LPS-stimulated RAW264.7 macrophages were further investigated. Results showed that GMPH significantly suppressed LPS-induced intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) production. GMPH reduced the production of prostaglandin E2 (PEG2) and the expression of cyclooxygenase-2 (COX-2) and cytosolic phospholipase A2 (cPLA2) in LPS-stimulated macrophages. GMPH also attenuated LPS-induced phosphorylation of MAPK (c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38) and protein kinase B (Akt). Furthermore, GMPH inhibited nuclear transcription factor kappa-B (NF-κB) activation by suppressing the nuclear translocation of NF-κB p65, which was markedly reversed by LY294002, an Akt inhibitor. These results demonstrated that GMPH exerts anti-inflammatory functions through the inactivation of MAPK and Akt in LPS-stimulated RAW264.7 macrophages, therefore may hold potential to ameliorate inflammation-related metabolic disorders.

The protective role of melatonin in chemotherapy-induced nephrotoxicity: a systematic review of non-clinical studies

BSTRACT Introduction: The aim of this study was to investigate the potential role of melatonin in the prevention of chemotherapy-induced nephrotoxicity at the preclinical level. Areas to be covered: To illuminate the possible role of melatonin in preventing chemotherapy-related nephrotoxicity, Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline was followed. A comprehensive search strategy was developed to include PubMed, Web of Science, Scopus, and Embase electronic databases from their inception to May 2018. Based on a set of prespecified inclusion and exclusion criteria, 21 non-clinical articles were ultimately included in the study. Expert opinion: Our findings clearly demonstrate that melatonin has a protective role in the prevention of chemotherapy-induced nephrotoxicity which may be caused by different chemotherapy agents such as cyclophosphamide, cisplatin, doxorubicin, methotrexate, oxaliplatin, etoposide, and daunorubicin. On the basis of current review of non-clinical studies, this protective effect of melatonin is attributed to different mechanisms such as reduction of oxidative stress, apoptosis, and inflammation. The findings presented in this review are based on non-clinical studies and thus conducting appropriate clinical trials to evaluate the real effectiveness of the concurrent use of chemotherapy agents with melatonin in the cancer patients is necessary.

Oral administration of Lentinus edodes β-glucans ameliorates DSS-induced ulcerative colitis in mice via MAPK-Elk-1 and MAPK-PPARγ pathways

To evaluate the anti-inflammatory effect of β-glucans from Lentinus edodes, and its molecular mechanism, the dextran sulfate sodium salt (DSS) induced colitis model of mice and the LPS-stimulated RAW264.7 cell inflammation model were used in this study. 40 ICR male mice were randomly divided into 4 groups: Control, DSS (DSS treated only), DSS + low-βGs (500 mg kg^-1 d^-1) and DSS + high-βGs (1000 mg kg^-1 d^-1). The body weight of the mice with Lentinus edodes β-glucan supplementation increased significantly compared to the DSS group and the disease activity index (DAI) was improved in both βG-treated groups. Compared with the DSS group, histopathological analysis showed that the infiltration of inflammatory cells of both βG-treated groups decreased significantly in colonic tissues. Furthermore, oral administration of β-glucans decreases the concentration of malondialdehyde (MDA) and myeloperoxidase (MPO) and inhibits the expression of iNOS and several inflammatory factors: TNF-α, IL-1β and IL-6 as well as nitric oxide (NO) of the colonic tissues. The mitogen-activated protein kinase (MAPK) pathway is closely related to the expression of pro-inflammatory factors. In the DSS-induced colitis model and the LPS-stimulated RAW264.7 cell model, βGs inhibited the expression of pro-inflammatory factors and blocked the phosphorylation of JNK/ERK1/2 and p38; βGs also suppress the phosphorylation of Elk-1 at Ser84 and the phosphorylation of PPARγ at Ser112. Altogether, these results suggest that Lentinus edodes βGs could inhibit the DSS-induced ulcerative colitis and decrease inflammatory factor expressions. The molecular mechanism may be involved in suppressing MAPK signaling and inactivation of Elk-1 and activation of PPARγ.

Nucleic acid aptamer application in diagnosis and therapy of colorectal cancer based on cell-SELEX technology

Nucleic acid aptamers are a class of high-affinity nucleic acid ligands. They serve as “chemical antibodies” since their high affinity and specificity. Nucleic acid aptamers are generated from nucleic acid random-sequence using a systematic evolution of ligands by exponential enrichment (SELEX) technology. SELEX is a process of effectively selecting aptamers from different targets. A newly developed cell-based SELEX technique has been widely used in biomarker discovery, early diagnosis and targeted cancer therapy, particular at colorectal cancer (CRC). Combined with nanostructures, nano-aptamer-drug delivery system was constructed for drug delivery. Various nanostructures functionalized with aptamers are highly efficient and has been used in CRC therapeutic applications. In the present, we introduce a cell- SELEX technique, and summarize the potential application of aptamers as biomarkers in CRC diagnosis and therapy. And some characteristics of aptamer-targeted nanocarriers in CRC have been expatiated. The challenges and perspectives for cell-SELEX are also discussed.

Characterization of a metabolomic profile associated with responsiveness to therapy in the acute phase of septic shock

The early metabolic signatures associated with the progression of septic shock and with responsiveness to therapy can be useful for developing target therapy. The Sequential Organ Failure Assessment (SOFA) score is used for stratifying risk and predicting mortality. This study aimed to verify whether different responses to therapy, assessed as changes in SOFA score at admission (T1, acute phase) and 48 h later (T2, post-resuscitation), are associated with different metabolite patterns. We examined the plasma metabolome of 21 septic shock patients (pts) enrolled in the Shockomics clinical trial (NCT02141607). Patients for which SOFA_T2 was >8 and Δ = SOFA_T1 − SOFA_T2 < 5, were classified as not responsive to therapy (NR, 7 pts), the remaining 14 as responsive (R). We combined untargeted and targeted mass spectrometry-based metabolomics strategies to cover the plasma metabolites repertoire as far as possible. Metabolite concentration changes from T1 to T2 (Δ = T2 − T1) were used to build classification models. Our results support the emerging evidence that lipidome alterations play an important role in individual patients’ responses to infection. Furthermore, alanine indicates a possible alteration in the glucose-alanine cycle in the liver, providing a different picture of liver functionality from bilirubin. Understanding these metabolic disturbances is important for developing any effective tailored therapy for these patients.

Lipopolysaccharide Adsorbed to the Bio-Corona of TiO2 Nanoparticles Powerfully Activates Selected Pro-inflammatory Transduction Pathways

It is known that the adsorption of bioactive molecules provides engineered nanoparticles (NPs) with novel biological activities. However, the biological effects of the adsorbed molecules may also be modified by the interaction with NP. Bacterial lipopolysaccharide (LPS), a powerful pro-inflammatory compound, is a common environmental contaminant and is present in several body compartments such as the gut. We recently observed that the co-incubation of LPS with TiO₂ NPs markedly potentiates its pro-inflammatory effects on murine macrophages, suggesting that, when included in a NP bio-corona, LPS activity is enhanced. To distinguish the effects of adsorbed LPS from those of the free endotoxin, a pellet fraction, denominated P25/LPS, was isolated by centrifugation from a mixture of P25 TiO₂ NP (128 µg/ml) and LPS (10 ng/ml) in the presence of fetal bovine serum. Western blot analysis of the pellet eluate indicated that the P25/LPS fraction contained, besides proteins, also LPS, pointing to the presence of LPS-doped NP. The effects of adsorbed or free LPS were then compared in Raw264.7 murine macrophages. RT-PCR was used to evaluate the induction of cytokine genes, whereas active, phosphorylated isoforms of proteins involved in signaling pathways were assessed with western blot. At a nominal LPS concentration of 40 pg/ml, P25/LPS induced the expression of both NF-κB and IRF3-dependent cytokines at levels comparable with those observed with free LPS (10 ng/ml), although with different time courses. Moreover, compared to free LPS, P25/LPS caused a more sustained phosphorylation of p38 MAPK and a more prolonged induction of STAT1-dependent genes. Cytochalasin B partially inhibited the induction of Tnfa by P25/LPS, but not by free LPS, and suppressed the induction of IRF3-dependent genes by either P25/LPS or free LPS. These data suggest that, when included in the bio-corona of TiO₂ NP, LPS exhibits enhanced and time-shifted pro-inflammatory effects. Thus, in assessing the hazard of NP in real life, the enhanced effects of adsorbed bioactive molecules should be taken into account.

Anti-inflammatory activity of cecropin-A2 from Musca domestica

This study aimed to investigate the anti-inflammatory activity of Musca domestica cecropin-A2 (Mdc-A2) toward Staphylococcus aureus (S. aureus) to learn more about their immunological functions. RAW264.7 cells were transfected with recombinant lentiviruses introduce pLEX-Mdc-A2into the RAW264.7 cell line (RAW-Mdc-A2). The RAW264.7 cell line with empty pLEX (RAW-pLEX) was produced in the same manner as a negative control. Real-time quantitative reverse transcription PCR (RT-PCR) was performed to analyze the mRNA expression of TNF-a, IL-1β, NFκB-1 and NFκB-2 in S. aureus-stimulated RAW-Mdc-A2 cells and RAW-pLEX cells in untreated cells and cells treated for 3 h, 6 h, 12 h and 24 h. RT-PCR was performed to analyze the mRNA expression of TNF-a, NFκB-1 and NFκB-2 stimulated by Lipoteichoic acid (LTA). Production of TNF-a was detected by enzyme-linked immunosorbent assay (ELISA). Colony counts were used to calculate the number of CFU per mL of cell culture supernatants. The results showed that compared to RAW-pLEX cells, stable transfection of Mdc-A2 in RAW264.7 cells stimulated by S. aureus significantly down-regulated the mRNA expression of TNF-a transcript variant 1 (TNF-a-tv-1) at 6 h and 12 h and the mRNA expression of TNF-a transcript variant 2 (TNF-a-tv-2) at 3 h, 6 h and 12 h. Compared to RAW-pLEX cells, stable transfection of Mdc-A2 in RAW264.7 cells stimulated by S. aureus significantly down-regulated the mRNA expression of IL-1β-T at 3 h, 6 h and 12 h as well as the mRNA expression of IL-1β at 3 h and 6 h. The expression and production of TNF-a and bacterial burden of cell culture supernatants were significantly down-regulated in RAW-Mdc-A2 cells stimulated by S. aureus, and the expression and production of TNF-a were significantly down-regulated in RAW-Mdc-A2 cells stimulated by LTA. Compared to RAW-pLEX cells, stable transfection of Mdc-A2 in RAW264.7 cells stimulated by S. aureus significantly down-regulated the mRNA expression of NFκB-1 at 3 h, 6 h and 12 h as well as the mRNA expression of NFκB-2 at 6 h. Additionally, stable transfection of Mdc-A2 in RAW264.7 cells stimulated by LTA significantly down-regulated the mRNA expression of NFκB-1. In conclusion, Mdc-A2 possesses potent anti-inflammatory activity and potent antimicrobial activity. Additionally, Mdc-A2 may interact with LTA and execute strong anti-inflammatory activity by blocking the activation of NF-κB signaling pathways.

Astragalus polysaccharides exerts immunomodulatory effects via TLR4-mediated MyD88-dependent signaling pathway in vitro and in vivo

Astragalus polysaccharides (APS), which is widely used as a remedy to promote immunity of breast cancer patients, can enhance immune responses and exert anti-tumor effects. In this study, we investigated the effects and mechanisms of APS on macrophage RAW 264.7 and EAC tumor-bearing mice. Griess reaction and ELISA assays revealed that the concentrations of nitric oxide, TNF-α, IL-1β and IL-6 were increased by APS. However, this effect was diminished in the presence of TAK-242 (TLR4 inhibitor) or ST-2825(MyD88 inhibitor). In C57BL/10J (TLR4^+/+wild-type) and C57BL/6J (MyD88^+/+wild-type) tumor-bearing mice, the tumor apoptosis rate, immune organ indexes and the levels of TNF-α, IL-1β and IL-6 in blood increased and the tumor weight decreased by oral administration of APS for 25 days. APS had no obvious effects on IL-12p70. However, these effects were not significant in C57BL/10ScNJ (TLR4-deficient) and C57BL/B6.129P2(SJL)-Myd88^m1.1Defr/J (MyD88-deficient) tumor-bearing mice. qRT-PCR and Western blot indicated that APS stimulated the key nodes in the TLR4-MyD88 dependent signaling pathway, including TLR4, MyD88, TRAF-6, NF-κB and AP-1, both in vitro and in vivo. However, TRAM was an exception. Moreover, TRAF-6 and NF-κB were not triggered by APS in gene-deficient tumor-bearing mice. Therefore, APS may modulate immunity of host organism through activation of TLR4-mediated MyD88-dependent signaling pathway.

Angiopoietin-Like Protein 7 Promotes an Inflammatory Phenotype in RAW264.7 Macrophages Through the P38 MAPK Signaling Pathway

Angiopoietin-like protein 7 (Angptl7) has been extensively studied for decades, but its potential immune functions have not been characterized. Hence, we investigated the relationship between Angptl7 and inflammation by using RAW264.7 monocyte/macrophage cells. The expression of genes encoding inflammation-associated factors cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), IL-6, IL-10, and transforming growth factor beta 1 (TGF-β1)) decreased after RAW264.7 cells were treated with anti-Angptl7 polyclonal antibody but increased after the cells were transfected with an Angptl7-expressing plasmid. Angptl7 overexpression enhanced phagocytosis and inhibited the proliferation of RAW264.7 cells. In addition, Angptl7 antagonized the anti-inflammatory effects of TGF-β1 and dexamethasone. Pathway analysis showed that Angptl7 promoted the phosphorylation of both p65 and p38, but only the P38 mitogen-activated protein kinase (MAPK) signaling pathway mediated Angptl7-associated inflammatory functions. Additionally, after 1 week of daily intraperitoneal injections of recombinant TNF-α in a mouse model of peripheral inflammation, Angptl7 expression increased in the mouse eyes. Thus, Angptl7 is a factor that promotes pro-inflammatory responses in macrophages through the P38 MAPK signaling pathway and represents a potential therapeutic target for treatment of inflammatory diseases.

Effect of lipid-bound apolipoprotein A-I cysteine mutant on ATF3 in RAW264.7 cells

Activating transcription factor 3 (ATF3) is a TLR-induced repressor that plays an important role in the inhibition of specific inflammatory signals. We previously constructed recombinant high density lipoproteins (rHDL) (including rHDL_WT, rHDL_M, rHDL₂₂₈ and rHDL₇₄) and found that rHDL₇₄ had a strong anti-inflammatory ability. In the present study, we investigate the roles of recombinant apolipoprotein A-I (ApoA-I) (rHDL_WT) and its cysteine mutant HDLs (rHDL_M, rHDL₂₂₈ and rHDL₇₄) on ATF3 function in RAW264.7 cells stimulated by lipopolysaccharide. Our results showed that compared with the LPS group, rHDL₇₄ can decrease the level of TNF-α and IL-6, whereas rHDL₂₂₈ increases their expression levels. RT-PCR and Western blotting results showed that compared with the LPS group, rHDL₇₄, rHDL_WT and rHDL_M can markedly increase the expression level of ATF3, whereas the level of ATF3 decreases in the rHDL₂₂₈ group. In summary, the different anti-inflammatory mechanisms of the ApoA-I cysteine mutants might be associated with the regulation of ATF3 level.

Evaluation of anti-inflammatory activity of compounds isolated from the rhizome of Ophiopogon japonicas

Background

Ophiopogon japonicas (L.f) Ker-Gawl has been used as a traditional Chinese medicine to cure acute and chronic inflammation and cardiovascular diseases including thrombotic diseases for thousands of years. Previous phytochemical studies showed that O. japonicus contained compounds with anti-inflammatory activity. The aim of this study was to identify and isolate compounds with anti-inflammatory activity from the rhizome of O. japonicas.

Methods

Compounds were isolated by various column chromatography and their structures were identified in terms of nuclear magnetic resonance spectrum (NMR) and mass spectrum (MS). To measure the anti-inflammatory effects of thirteen compounds in LPS-induced RAW 264.7 macrophage cells, we used the following methods: cell viability assay, nitric oxide assay, enzyme-linked immunosorbent assay, quantitative real-time PCR analysis and western blotting analysis.

Results

One new and twelve known compounds (mainly homoisoflavonoids) were extracted from O. japonicas, in which 4′-O-Demethylophiopogonanone E (10) was considered as a new compound, additionally, compounds 4-O-(2-Hydroxy-1- hydroxymethylethyl)-dihydroconiferyl alcohol (2) and 5,7-dihydroxy-6-methyl-3-(2′, 4′-dihydroxybenzyl) chroman-4-one (12) were isolated from the rhizome of O. japonicas for the first time. The isolated compounds Oleic acid (3), Palmitic acid (4), desmethylisoophiopogonone B [5,7-dihydroxy-3-(4′-hydroxybenzyl)-8- methyl- chromone] (5), 5,7-dihydroxy-6-methyl-3-(4′-hydroxybenzyl) chromone (7) and 10 significantly suppressed the production of NO in LPS-induced RAW 264.7 cells. Especially compound 10 showed the strongest effect against the production of the pro-inflammatory cytokine IL-1β and IL-6 with the IC₅₀ value of 32.5 ± 3.5 μg/mL and 13.4 ± 2.3 μg/mL, respectively. Further analysis elucidated that the anti-inflammatory activity of compound 10 might be exerted through inhibiting the phosphorylation of ERK1/2 and JNK in MAPK signaling pathways to decrease NO and pro-inflammatory cytokines production.

Conclusions

Our results indicated that 4′-O-Demethylophiopogonanone E can be considered as a potential source of therapeutic medicine for inflammatory diseases.

Tumor necrosis factor-α: a key contributor to intervertebral disc degeneration

Intervertebral disc (IVD) degeneration (IDD) is the most common cause leading to low back pain (LBP), which is a highly prevalent, costly, and crippling condition worldwide. Current treatments for IDD are limited to treat the symptoms and do not target the pathophysiology. Tumor necrosis factor-α (TNF-α) is one of the most potent pro-inflammatory cytokines and signals through its receptors TNFR1 and TNFR2. TNF-α is highly expressed in degenerative IVD tissues, and it is deeply involved in multiple pathological processes of disc degeneration, including matrix destruction, inflammatory responses, apoptosis, autophagy, and cell proliferation. Importantly, anti-TNF-α therapy has shown promise for mitigating disc degeneration and relieving LBP. In this review, following a brief description of TNF-α signal transduction, we mainly focus on the expression pattern and roles of TNF-α in IDD, and summarize the emerging progress regarding its inhibition as a promising biological therapeutic approach to disc degeneration and associated LBP. A better understanding will help to develop novel TNF-α-centered therapeutic interventions for degenerative disc disease.

The effects of Qi Teng Xiao Zhuo granules, traditional Chinese medicine, on the expression of genes in chronic glomerulonephritis rats

BACKGROUND AND AIM

Chronic glomerulonephritis (CGN) is a primary glomerular disease that is related to immune-mediated inflammatory diseases. Qi Teng Xiao Zhuo granules have been proposed as a prescription of traditional Chinese medicine for treatment of CGN, but the comprehensive molecular mechanism underlying this therapeutic effect is not clear to date. The aim of this study was to evaluate and analyze the possible roles and molecular mechanisms of Qi Teng Xiao Zhuo granule-mediated treatment of CGN induced by adriamycin in rats.

METHODS

For gene expression analysis, four samples of glomerular tissue from rats in the Qi Teng Xiao Zhuo granule group and four samples each from the adriamycin treated and control groups were hybridized with Agilent Rat 4×44K whole genome microarrays. KEGG and Gene Ontology (GO) analyses and LIMMA, String and Cytoscape software were used to analyze the functional microarray data and screen differentially expressed genes. Hub genes were identified using Pathway Studio software. Real-time PCR was performed to verify the selected genes.

RESULTS

Microarray gene expression analysis showed that Pnoc, Cacfd1, Fos, Igll1, Lcn2, and Syk were among the most downregulated genes in the Qi Teng Xiao Zhuo granule group compared with the adriamycin treated group, whereas Cyp2c7, Hsd3b6, Acsm5, and Ugt2b15 were significantly upregulated. Functional analysis demonstrated that metabolism of xenobiotics by cytochrome P450, the B cell receptor signaling pathway, and cytokine-cytokine receptor interaction pathways were significantly downregulated in the Qi Teng Xiao Zhuo granule group and that GO terms related to positive regulation of immune response, immune response-activating signal transduction, cell differentiation, cell cycle, proliferation, and adhesion were significantly affected. Fos and Syk were considered to be potential hub genes.

CONCLUSIONS

In the adriamycin-induced CGN rat model, comprehensive molecular mechanisms were involved with complex gene expression alterations containing many altered pathways and GO terms. However, how Qi Teng Xiao Zhuo granules regulate these events warrants further investigation.

Involvement of Nrf2-mediated heme oxygenase-1 expression in anti-inflammatory action of chitosan oligosaccharides through MAPK activation in murine macrophages

Chitosan and its derivatives have been reported to have anti-inflammatory effects in vitro and in vivo. It is also suggested that chitosan and its derivatives could be up-regulating heme oxygenase-1 (HO-1) in different models. However, the up-regulation of HO-1 by chitosan oligosaccharides (COS) remains unexplored in regard to anti-inflammatory action in lipopolysaccharide (LPS)-stimulated murine macrophages (RAW264.7 cells). Treatment with COS induced HO-1 expression in LPS-stimulated RAW264.7 cells, whereas the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) was decreased. Pretreatment with ZnPP, a HO-1 inhibitor, reduced the COS-mediated anti-inflammatory action. HO-1 induction is mediated by activating the nuclear translocation of NF-E2-related factor 2 (Nrf2) using COS. Moreover, COS increased the phosphorylation of extracellular signal regulated kinase (ERK1/2), c-Jun N-terminal kinase/stress-activated protein kinase (JNK), and p38 MAPK. However, specific inhibitors of ERK, JNK, and p38 reduced COS-mediated nuclear translocation of Nrf2. Therefore, HO-1 induction also decreased in RAW264.7 cells. Collectively, COS exert an anti-inflammatory effect through Nrf2/MAPK-mediated HO-1 induction.

The Anti-Inflammatory Effects of Interferon Tau by Suppressing NF-κB/MMP9 in Macrophages Stimulated with Staphylococcus aureus

Previous studies have reported that interferon tau (IFNT) significantly mitigates tissue inflammation. However, this effect and its regulating pathways have not been reported for Staphylococcus aureus-induced inflammation. In this study, RAW 264.7 cells stimulated with S. aureus were used to identify the anti-inflammatory effects and mechanism of IFNT. First, IFNT was found to be noncytotoxic to macrophages treated with the high dose of 200 ng/mL IFNT. ELISA and qPCR revealed that IFNT decreased the expression of proinflammatory cytokines such as TNF-α, IL-1β, and IL-6. TLR2, which is involved in the immune response during S. aureus infection, directly affected NF-κB pathway activation and was also downregulated by IFNT. Subsequent Western blotting showed that the phosphorylation of IκBα and NF-κB p65 was inhibited by IFNT. Therefore, although the MMP9 levels were significantly downregulated in a dose-dependent manner by IFNT, little change in MMP2 was observed in S. aureus-stimulated RAW 264.7 cells. Furthermore, PDTC, an inhibitor of NF-κB, also significantly decreased MMP9 levels by inhibiting NF-κB p65 activation. All of these findings strongly suggested that IFNT suppresses the NF-κB/MMP9 signal transduction pathway and subsequently exerts its anti-inflammatory effects in S. aureus-stimulated RAW 264.7 cells.