Ailanthoidol suppresses lipopolysaccharide-stimulated inflammatory reactions in RAW264.7 cells and endotoxin shock in mice

Natural products as IL-6 inhibitors for inflammatory diseases: Synthetic and SAR perspective

Interleukin-6 (IL-6), a pleiotropic cytokine, plays a pivotal role in the pathophysiology of various diseases including diabetes, atherosclerosis, Alzheimer's disease, multiple myeloma, rheumatoid arthritis, and prostate cancer. The signaling pathways associated with IL-6 offer promising targets for therapeutic interventions in inflammatory diseases and IL-6-dependent tumors. Although certain anti-IL-6 monoclonal antibodies are currently employed clinically, their usage is hampered by drawbacks such as high cost and potential immunogenicity, limiting their application. Thus, the imperative arises to develop novel small non-peptide molecules acting as IL-6 inhibitors. Various natural products derived from diverse sources have been investigated for their potential to inhibit IL-6 activity. Nevertheless, these natural products remain inadequately explored in terms of their structure-activity relationships. In response, our review aims to provide syntheses and structure activity perspective of natural IL-6 inhibitors. The comprehensive amalgamation of information presented in this review holds the potential to serve as a foundation for forthcoming research endeavors by medicinal chemists, facilitating the design of innovative IL-6 inhibitors to address the complexities of inflammatory diseases.

Suppression of the Proliferation of Huh7 Hepatoma Cells Involving the Downregulation of Mutant p53 Protein and Inactivation of the STAT 3 Pathway with Ailanthoidol

Ailanthoidol (ATD) has been isolated from the barks of Zanthoxylum ailanthoides and displays anti-inflammatory, antioxidant, antiadipogenic, and antitumor promotion activities. Recently, we found that ATD suppressed TGF-β1-induced migration and invasion of HepG2 cells. In this report, we found that ATD exhibited more potent cytotoxicity in Huh7 hepatoma cells (mutant p53: Y220C) than in HepG2 cells (wild-type p53). A trypan blue dye exclusion assay and colony assay showed ATD inhibited the growth of Huh7 cells. ATD also induced G1 arrest and reduced the expression of cyclin D1 and CDK2. Flow cytometry analysis with Annexin-V/PI staining demonstrated that ATD induced significant apoptosis in Huh7 cells. Moreover, ATD increased the expression of cleaved PARP and Bax and decreased the expression of procaspase 3/8 and Bcl-xL/Bcl-2. In addition, ATD decreased the expression of mutant p53 protein (mutp53), which is associated with cell proliferation with the exploration of p53 siRNA transfection. Furthermore, ATD suppressed the phosphorylation of the signal transducer and activator of transcription 3 (STAT3) and the expression of mevalonate kinase (MVK). Consistent with ATD, the administration of S3I201 (STAT 3 inhibitor) reduced the expression of Bcl-2/Bcl-xL, cyclin D1, mutp53, and MVK. These results demonstrated ATD’s selectivity against mutp53 hepatoma cells involving the downregulation of mutp53 and inactivation of STAT3.

Ailanthoidol, a Neolignan, Suppresses TGF-β1-Induced HepG2 Hepatoblastoma Cell Progression

Ailanthoidol (ATD), a neolignan, possessed an antitumor promotion effect in the mouse skin model in our previous investigation. However, other antitumor properties remain to be elucidated. Liver cancer is a major cause of death in the world, and its prognosis and survival rate are poor. Therefore, the prevention and therapy of liver cancer have received much attention. TGF (transforming growth factor)-β1, a cytokine, plays a critical role in the progression of liver cancer. This study determined the inhibitory effects of ATD on the migration and invasion induced by TGF-β1 in HepG2 hepatoblastoma cells. Furthermore, ATD reduced the TGF-β1-promoted colony number of HepG2 hepatoblastoma cells. In addition to reversing TGF-β1-induced cell scattering, ATD suppressed TGF-β1-induced expression of integrin α3, vimentin, N-cadherin, and matrix metalloproteinase 2 (MMP2). Finally, this study found that ATD significantly inhibited TGF-β1-promoted phosphorylation of p-38 mitogen-activated protein kinase (MAPK) and Smad 2. Furthermore, the administration of SB203580 (p38MAPK inhibitor) suppressed TGF-β1-induced expression of integrin α3, N-cadherin, and MMP2. These results demonstrate a novel mechanism of ATD against progression of liver cancer.

Toxoplasma ROP16I/III ameliorated inflammatory bowel diseases via inducing M2 phenotype of macrophages

BACKGROUND

Inflammatory bowel disease (IBD) is characterized by chronic and non-specific inflammation of the intestinal mucosa and mainly includes ulcerative colitis and Crohn's disease.

AIM

To explore the beneficial effect of ToxoROP16_I/III-induced M2 phynotype macrophages in homeostasis of IBDs through downregulation of M1 inflammatory cells.

METHODS

RAW264.7 macrophages stimulated by lipopolysaccharide (LPS) (M1 cells) were co-cultured with Caco-2 cells as an inflammatory model of IBD in vitro. The expression of ToxoROP16_I/III was observed in RAW264.7 macrophages that were transfected with pEGFP-rop16_I/III. The phenotypes of M2 and M1 macrophage cells were assessed by quantitative real-time reverse transcriptase polymerase chain reaction and the expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, transforming growth factor (TGF)-β1, IL-10, inducible nitric oxide synthase (iNOS), and arginase-1 (Arg-1) was detected. The expression of iNOS, Arg-1, signal transducer and activator of transcription 3 (Stat3), p-Stat3, Stat6, p-Stat6, programmed death ligand-2 (PD-L2), caspase-3, -8, and -9 was analyzed by Western blotting, and Griess assays were performed to detect nitric oxide (NO). TNF-α, IL-1β, IL-6, TGF-β1, and IL-10 expression in the supernatants was detected by enzyme-linked immunosorbent assay, and Caco-2 cell apoptosis was determined by flow cytometry after mixing M1 cells with M2 cells in a Caco-2 cell co-culture system.

RESULTS

M1 cells exhibited significantly increased production of iNOS, NO, TNF-α, IL-1β, and IL-6, while ToxoROP16_I/III induced macrophage bias to M2 cells in vitro, showing increased expression of Arg-1, IL-10 and TGF-β1 and elevated production of p-Stat3 and p-Stat6. The mixed M1 and M2 cell culture induced by ToxoROP16_I/III exhibited decreased production of NO and iNOS and upregulated expression of Arg-1 and PD-L2. Accordingly, Caco-2 cells became apoptotic, and apoptosis-associated proteins such as caspase-3, -8 and -9 were dampened during co-culture of M1 and M2 cells. Flow cytometry analysis showed that co-culture of M1 cells with Caco-2 cells facilitated the apoptosis of Caco-2 cells, but co-culture of M1 and M2 cells alleviated Caco-2 cell apoptosis.

CONCLUSION

ToxoROP16_I/III-induced M2 macrophages inhibited apoptosis of Caco-2 cells caused by M1 macrophages. This finding may help gain a better understanding of the underlying mechanism and represent a promising therapeutic strategy for IBDs.

Semi-synthesis, structural modification and biological evaluation of 5-arylbenzofuran neolignans

5-Arylbenzofuran neolignans, a newfound class of natural products, were semi-synthesized, and a series of derivatives were designed, synthesized and evaluated for cytotoxicity.

New horizon in the treatment of sepsis: a systematic review of alternative medicine

BackgroundDespite great advancement in treatment of sepsis, mortality of sepsis remains unacceptably high, even with the modern antibiotic and intensive care technologies. Considering the key role of immune dysfunction in sepsis pathophysiology, different treatments were evaluated, but failed to improve survival of patients. Natural remedies have been tested in various studies to overcome sepsis. In this study, we aim to review some of the evidence from clinical, in vitro and in vivo studies about the effect of alternative medicine on sepsis management. MethodsThe following databases were searched up to March 2014: PubMed, Scopus, Web of Science, Ovid and Google Scholar using combination of Mesh term. All in vitro and in vivo studies, also clinical trials, published in English, which evaluated alternative medicine in management of sepsis were included. Results Out of 95 relevant studies, the inclusion criteria were met for 79 cases. Among them, 18 studies were performed on humans. The most herbal medicine, including Xubijing (n=10) and then Rhubarb (n=3). Most of the reviewed botanical medicines modulate the immune system. Reduction of mortality was also reported in studies. ConclusionsModulation of immune system, anti-inflammatory activities and improvement of survival were the action of herbal medicine. A monovalent approach is not enough for treatment of sepsis, we recommend further studies to identify active component of herbal and use them in combination. Also an animal model of sepsis does not exactly mimic human sepsis, so more clinical studies should be performed. With no new drug on the horizon, herbal medicine will be promising for treatment of sepsis.

Anti-inflammatory effects and molecular mechanisms of 8-prenyl quercetin

SCOPE

8-prenyl quercetin (PQ) is a typical prenylflavonoid distributed in plant foods. It shows higher potential bioactivity than its parent quercetin (Q) although the mechanisms are not fully understood. This study aims to clarify the anti-inflammatory effects and molecular mechanisms of PQ in cell and animal models, compared to Q.

METHODS AND RESULTS

RAW264.7 cells were treated with PQ or Q to investigate the influence on the production of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and protein kinases by Western blotting. Nitric oxide (NO) and prostaglandin E2 (PGE2 ) were measured by the Griess method and ELISA, respectively. Cytokines were assayed by the multiplex technology. Mouse paw edema was induced by LPS. The results revealed that PQ had stronger inhibition on the production of iNOS, COX-2, NO, PGE2 , and 12 kinds of cytokines, than Q. PQ also showed in vivo anti-inflammatory effect by attenuating mouse paw edema. Molecular data revealed that PQ had no competitive binding to Toll-like receptor 4 with LPS, but directly targeted SEK1-JNK1/2 (where SEK is stress-activated protein kinase and JNK1/2 is Jun-N-terminal kinase 1/2) and MEK1-ERK1/2 (where ERK is extracellular signal regulated kinase).

CONCLUSION

PQ as a potential inhibitor revealed anti-inflammatory effect in both cell and animal models at least by targeting SEK1-JNK1/2 and MEK1-ERK1/2.

Salvia miltiorrhiza: Traditional medicinal uses, chemistry, and pharmacology

Salvia miltiorrhiza Bunge (SM) is a very popular medicinal plant that has been extensively applied for many years to treat various diseases, especially coronary heart diseases and cerebrovascular diseases, either alone or in combination with other Chinese plant-based medicines. Although a large number of studies on SM have been performed, they are scattered across a variety of publications. The present review is an up-to-date summary of the published scientific information about the traditional uses, chemical constituents, pharmacological effects, side effects, and drug interactions with SM, in order to lay the foundation for further investigations and better utilization of SM. SM contains diverse chemical components including diterpenoid quinones, hydrophilic phenolic acids, and essential oils. Many pharmacological studies have been done on SM during the last 30 years, focusing on the cardiovascular and cerebrovascular effects, and the antioxidative, neuroprotective, antifibrotic, anti-inflammatory, and antineoplastic activities. The research results strongly support the notion that SM has beneficial therapeutic properties and has a potential of being an effective adaptogenic remedy.

Adenosine 5'-monophosphate ameliorates D-galactosamine/lipopolysaccharide-induced liver injury through an adenosine receptor-independent mechanism in mice

D-galactosamine (GalN)/lipopolysaccharide (LPS)-induced lethality and acute liver failure is dependent on endogenously produced inflammatory cytokines. Adenosine has been proven to be a central role in the regulation of inflammatory response. It is not entirely clear that which adenosine action is actually crucial to limiting inflammatory tissue destruction. Here we showed that GalN/LPS challenge elevated hepatic adenosine and induced lethality in adenosine receptor-deficient mice with equal efficiency as wild-type mice. In GalN/LPS-treated mice, pretreatment with adenosine 5'-monophosphate (5'-AMP) significantly elevated hepatic adenosine level and reduced mortality through decreasing cytokine and chemokine production. In RAW264.7 cells, 5'-AMP treatment inhibited the production of inflammatory cytokines, which is not mediated through adenosine receptors. 5'-AMP failed to attenuate LPS-induced nuclear factor-κB (NF-κB) p65 nuclear translocation, but reduced LPS-induced recruitment of NF-κB p65 to inflammatory gene promoters and decreased LPS-induced enrichment of H3K4 dimethylation at the tumor necrosis factor-α (TNF-α) promoter, which was involved in 5'-AMP-induced elevation of cellular adenosine and a decline of methylation potential. In vitro biochemical analysis revealed that adenosine directly attenuated recruitment of NF-κB to the TNF-α and interleukin-6 promoters. Our findings demonstrate that 5'-AMP-inhibiting inflammatory response is not mediated by adenosine receptors and it may represent a potential protective agent for amelioration of LPS-induced liver injury.

2-(4-Hydroxyphenyl)-5-(3-Hydroxypropenyl)-7-Methoxybenzofuran, a Novel Ailanthoidol Derivative, Exerts Anti-Inflammatory Effect through Downregulation of Mitogen-Activated Protein Kinase in Lipopolysaccharide-Treated RAW 264.7 Cells

We reported that ailanthoidol, a neolignan from Zanthoxylum ailanthoides and Salvia miltiorrhiza Bunge, inhibited inflammatory reactions by macrophages and protected mice from endotoxin shock. We examined the anti-inflammatory activity of six synthetic ailanthoidol derivatives (compounds 1-6). Among them, compound 4, 2-(4-hydroxyphenyl)-5-(3-hydroxypropenyl)-7-methoxybenzofuran, had the lowest IC50 value concerning nitric oxide (NO) release from lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Compound 4 suppressed the generation of prostaglandin (PG) E2 and the expression of inducible NO synthase and cyclooxygenase (COX)-2 induced by LPS, and inhibited the release of LPS-induced pro-inflammatory cytokines from RAW264.7 cells. The underlying mechanism of compound 4 on anti-inflammatory action was correlated with the down-regulation of mitogen-activated protein kinase and activator protein-1 activation. Compound 4 is potentially an effective functional chemical candidate for the prevention of inflammatory diseases.

XH-14, a novel danshen methoxybenzo[b]furan derivative, exhibits anti-inflammatory properties in lipopolysaccharide-treated RAW 264.7 cells

Background

XH-14 isolated from Salvia miltiorrhiza is a bioactive component and adenosine antagonist. In the present study, we evaluated anti-inflammatory properties of XH-14 in murine macrophages.

Methods

RAW 264.7 murine macrophage cell line was cultured with various concentrations of XH-14 in the absence or presence of lipopolysaccharide (LPS). LPS-induced release and mRNA expression of inflammatory mediators were examined by ELISA and real-time PCR. The modification of signal pathways involved in inflammatory reactions was determined by Western blotting analysis.

Results

XH-14 suppressed the generation of nitric oxide (NO) and prostaglandin E₂, and the expression of inducible NO synthase and cyclooxygenase-2 induced by LPS. Similarly, XH-14 inhibited the release of pro-inflammatory cytokines induced by LPS in RAW 264.7 cells. The underlying mechanism of XH-14 on anti-inflammatory action was correlated with down-regulation of mitogen-activated protein kinase and activator protein-1 activation.

Conclusions

XH-14 inhibits the production of several inflammatory mediators and so might be useful for the treatment of various inflammatory diseases.