3α-Angeloyloxy-ent-kaur-16-en-19-oic Acid Isolated from Wedelia trilobata L. Alleviates Xylene-Induced Mouse Ear Edema and Inhibits NF-κB and MAPK Pathway in LPS-Stimulated Macrophages

From Hit to Lead: Discovery of First-In-Class Furanone Glycoside D228 Derived from Chimonanthus salicifolius for the Treatment of Inflammatory Bowel Disease

TNFα and related inflammatory factor antibody drugs have been orchestrated for the treatment of inflammatory bowel disease (IBD). However, antibody drugs elicited inevitable disadvantages and small molecule drugs are in an urgent need. Herein, we described the discovery, design, synthesis, and SAR studies from furanone glycoside compound Phoenicein (hit) isolated from Chimonanthus salicifolius to D228 (lead). Remarkably, D228 exhibited good inhibitory activity on B and T lymphocyte and excellent anti-IBD efficacy in vivo. Mechanistically, D228 alleviated the inflammation response by downregulating the MyD88/TRAF6/p38 signaling. Importantly, the relationship of D228, Phoenicein, and their aglycone 7a was deduced: D228 could be considered as a prodrug and metabolized to intermediate Phoenicein. In turn, Phoenicein released their shared active aglycone 7a. Additionally, D228 demonstrated good and balanced profiles of safety and efficacy both in vitro and in vivo. These results suggested that D228 could be used as an ideal lead and potentially utilized for IBD chemotherapy.

Anti-inflammatory effects and related mechanisms in vitro and in vivo of Hedychium coccineum rhizome essential oil

ETHNOPHARMACOLOGICAL RELEVANCE

Hedychium coccineum rhizome is an anti-inflammatory ethnomedicine used to remedy inflammation-related swelling and bronchial asthma.

AIM OF THE STUDY

The study aimed to analyze the phytochemical constituents of H. coccineum rhizome essential oil (EO) and evaluate its in vitro and in vivo anti-inflammatory effects and underlying mechanisms.

MATERIALS AND METHODS

Phytochemical constituents of H. coccineum rhizome EO were analyzed using GC-FID/MS. In RAW264.7 macrophages induced by LPS, blockade of PGE2, NO, IL-1β, IL-6, and TNF-α secretion by H. coccineum rhizome EO was measured, and then Western blot, qRT-PCR, and immunofluorescent staining were used to evaluate its underlying mechanisms. Moreover, we used the xylene-induced ear edema model for testing anti-inflammatory potential in vivo and examined auricular swelling as well as tissue and serum contents of IL-1β, IL-6, and TNF-α.

RESULTS

EO's main components were E-nerolidol (40.5%), borneol acetate (24.8%), spathulenol (4.5%), linalool (3.8%), elemol (3.5%), and borneol (3.4%). In RAW264.7 cells stimulated by LPS, EO downregulated the expression of pro-inflammatory enzyme (iNOS and COX-2) genes and proteins, thereby suppressing pro-inflammatory mediators (NO and PGE2) secretion. Simultaneously, it reduced TNF-α, IL-1β, and IL-6 release by downregulating their mRNA expression. Besides, H. coccineum EO attenuated LPS-stimulated activation of NF-κB (by reducing IκBα phosphorylation and degradation to inhibit NF-κB nuclear translocation) and MAPK (by downregulating JNK, p38, and ERK phosphorylation). In xylene-induced mouse ear edema, EO relieved auricular swelling and lowered serum and tissue levels of TNF-α, IL-1β, and IL-6.

CONCLUSIONS

H. coccineum EO had powerful in vivo and in vitro anti-inflammatory effects by inhibiting MAPK and NF-κB activation. Hence, H. coccineum EO should have great potential for application in the pharmaceutical field as a novel anti-inflammatory agent.

Polygonum Cuspidatum Alcohol Extract Exerts Analgesic Effects via the MAPK/ERK Signaling Pathway

Objective

Traditional Chinese medicine Polygonum cuspidatum (PC) has significant effects on reducing pain. In this study, we investigated the analgesic effects of the alcohol extract of PC on three types of inflammatory pain and explored its mechanism.

Methods

Potential targets for the analgesic effects of the main active components of PC alcohol extract were screened by network pharmacology and molecular docking. Three different inflammatory pain mouse models (acetic acid twisting, formalin foot swelling, and xylene ear swelling) were used to study the analgesic effects of PC. The expression of latent signaling pathways in L4-6 spinal cord tissues in formalin foot swelling mice was evaluated using real-time qPCR (RT-qPCR), Western blot (WB), and immunohistochemistry (IHC) analyses.

Results

Network pharmacology analysis shows that PC analgesic mechanism is related to the MAPK/ERK signaling pathway. The five main active components of PC have good docking ability with JNK and p38. PC alcohol extract significantly reduced the pain behavior and alleviated inflammatory reactions in three mouse models, inhibited the mRNA and protein phosphorylation levels of JNK, ERK, p38, and CREB in spinal cord tissues.

Conclusion

PC alcohol extract can inhibit inflammation and alleviate pain, which is related to its inhibition of the MAPK/ERK signaling pathway in spinal cord. Thus, PC alcohol extract is a promising candidate for pain treatment.

Hedychium flavum flower essential oil: Chemical composition, anti-inflammatory activities and related mechanisms in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Hedychium flavum, an ornamental, edible, and medicinal plant, is extensively cultivated as a source of aromatic essential oils (EO). Its flower is a traditional Chinese medicine for treating inflammation-related diseases like indigestion, diarrhea, and stomach pain. In particular, H. flavum flower EO has been used in cosmetics and as an aromatic stomachic to treat chronic gastritis in China.

AIM OF THE STUDY

This research aimed to analyze H. flavum flower EO's chemical composition and explore its anti-inflammatory activities and related mechanisms in vitro and in vivo.

MATERIALS AND METHODS

EO's chemical composition was determined by GC-FID/MS analysis. For in vitro test, the anti-inflammatory activity of EO was demonstrated by measuring the LPS-induced release of NO, PGE₂, IL-1β, TNF-α, and IL-6 in RAW264.7 macrophages, and then its related mechanisms were explored using qRT-PCR, western blot, and immunofluorescent staining analysis. Next, EO's in vivo anti-inflammatory potential was further evaluated using a xylene-induced ear edema model, in which ear swelling and TNF-α, IL-6, and IL-1β levels in serum and tissue were examined.

RESULTS

The main components of EO were β-pinene (20.2%), α-pinene (9.3%), α-phellandrene (8.3%), 1,8-cineole (7.1%), E-nerolidol (5.4%), limonene (4.4%), borneol (4.1%), and β-caryophyllene (3.7%). For the anti-inflammatory activities in vitro, EO dramatically reduced the LPS-stimulated NO and PGE₂ release by suppressing the mRNA and protein expression of iNOS and COX-2. Meanwhile, it remarkably decreased IL-6, TNF-α, and IL-1β production by inhibiting their mRNA levels. Related mechanism studies indicated that it not only inhibited IκBα phosphorylation and degradation, leading to blockade of NF-κB nuclear transfer but also suppressed MAPKs (ERK, p38, and JNK) phosphorylation in LPS-stimulated RAW264.7 cells. Further in vivo assay showed that EO ameliorated xylene-induced ear edema in mice and reduced TNF-α, IL-6, and IL-1β levels in serum and tissue.

CONCLUSIONS

H. flavum EO exerted significant anti-inflammatory activity in vivo and in vitro, and its mechanism of action is related to the inhibition of MAPK and NF-κB activation. Thus, H. flavum EO could be considered a novel and promising anti-inflammatory agent and possess high potential for utilization in the pharmaceutical field.

Synthesis and Biological Evaluation of Gentiopicroside Derivatives as Novel Cyclooxygenase-2 Inhibitors with Anti-Inflammatory Activity

Purpose

Nonsteroidal anti-inflammatory drugs cause a series of adverse reactions. Thus, the search for new cyclooxygenase-2 selective inhibitors have become the main direction of research on anti-inflammatory drugs. Gentiopicroside is a novel selective inhibitor of cyclooxygenase-2 from Chinese herbal medicine. However, it is highly hydrophilic owing to the presence of the sugar fragment in its structure that reduces its oral bioavailability and limits efficacy. This study aimed to design and synthesize novel cyclooxygenase-2 inhibitors by modifying gentiopicroside structure and reducing its polarity.

Materials and Methods

We introduced hydrophobic acyl chloride into the gentiopicroside structure to reduce its hydrophilicity and obtained some new derivatives. Their in vitro anti-inflammatory activities were evaluated against NO, TNF-α, PGE₂, and IL-6 production in the mouse macrophage cell line RAW264.7 stimulated by lipopolysaccharide. The in vivo inhibitory activities were further tested against xylene-induced mouse ear swelling. Molecular docking predicted that whether new compounds could effectively bind to target protein cyclooxygenase-2. The inhibitory activity of new compounds to cyclooxygenase-2 enzyme were verified by the in vitro experiment.

Results

A total of 21 novel derivatives were synthesized, and exhibit lower polarities than the gentiopicroside. Most compounds have good in vitro anti-inflammatory activity. The in vivo activity results demonstrated that 8 compounds were more active than gentiopicroside. The inhibition rate of some compounds was higher than celecoxib. Molecular docking predicted that 6 compounds could bind to cyclooxygenase-2 and had high docking scores in accordance with their potency of the anti-inflammatory activity. The confirmatory experiment proved that these 6 compounds had significant inhibitory effect against cyclooxygenase-2 enzyme. Structure-activity relationship analysis presumed that the para-substitution with the electron-withdrawing groups may benefit the anti-inflammatory activity.

Conclusion

These gentiopicroside derivatives especially PL-2, PL-7 and PL-8 may represent a novel class of cyclooxygenase-2 inhibitors and could thus be developed as new anti-inflammatory agents.

Anti-inflammatory effects of Torin2 on lipopolysaccharide-treated RAW264.7 murine macrophages and potential mechanisms

Context

Torin2 has various pharmacological properties. However, its anti-inflammatory activity has not been reported.

Objective

This study focused on the potential anti-inflammatory properties of Torin2 in lipopolysaccharide (LPS)-evoked RAW264.7 murine macrophages. The study aimed to shed light on the molecular mechanisms that ameliorate these effects.

Methods

Torin2 was applied to 100 ng/mL lipopolysaccharide-induced RAW 264.7 macrophages in vitro. Nitric oxide (NO) levels were detected using the Griess reagent kit. Prostaglandin E2 (PGE2), pro-inflammatory cytokines interleukin (IL)-1β, interleukin (IL)-6, and tumor necrosis factor in the supernatant fraction were determined using enzyme-linked immunosorbent assay (ELISA). Gene expression of pro-inflammatory cytokines, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) were tested using real-time quantitative polymerase chain reaction (qPCR). Cyclooxygenase-2 and inducible nitric oxide synthase proteins, phosphorylation of mitogen-activated protein kinase (MAPK) subgroups, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38, I-kappa-B-alpha (IκBα), and nuclear factor-kappa-B (NF-κB), and activation in extracts were detected via western blotting. Nuclear factor-kappa-B/p65 nuclear translocation was tested using an immunofluorescence assay.

Results

The results demonstrated that pre-treatment with Torin2 profoundly attenuated the lipopolysaccharide-stimulated levels of nitric oxide and prostaglandin E2, pro-inflammatory cytokines, messenger ribonucleic acid (mRNA), and protein expression of cyclooxygenase-2 and inducible nitric oxide synthase. Collectively, Torin2 pre-treatment notably weakened lipopolysaccharide-induced damage by reducing the phosphorylation of nuclear factor-kappa-B, p38, c-Jun N-terminal kinase, extracellular signal-regulated kinase proteins, and nuclear factor-kappa-B/p65 nuclear translocation.

Conclusion

Numerous pieces of evidence indicated that Torin2 reversed inflammatory activation by regulating nuclear factor-kappa-B and mitogen-activated protein kinase signaling pathways and provided a tentative potential candidate for preventing and treating inflammatory diseases.

Dietary resveratrol alleviated lipopolysaccharide-induced ileitis through Nrf2 and NF-κB signalling pathways in ducks (Anas platyrhynchos)

Gram-negative bacteria contamination of feed can occur at all the stage of feed production, storage, transportation and utilization. Lipopolysaccharide (LPS) is a major toxic metabolite of Gram-negative bacteria. The aim of this study was to explore the effect of dietary resveratrol on the duck ileitis caused by LPS and its optimum addition level in diet. The results showed that LPS-induced duck ileitis with the destruction of intestinal structure, oxidative stress, mitochondrial dysfunction, inflammatory response and permeability alteration. Dietary resveratrol alleviated LPS-induced intestinal dysfunction and the increase of intestinal permeability by linearly increasing mRNA levels of tight junction protein genes (Claudin-1, Occludin-1, ZO-1) (p < 0.05) and protein expression of Claudin-1 (p < 0.01). In addition, dietary resveratrol improved the antioxidant capacity of duck ileum by reducing the production of MDA and increasing the activity of T-SOD (p < 0.01) and CAT. Lipopolysaccharide increased Keap1 at mRNA and protein level (p < 0.01) and decreased the protein level of Nrf2 (p < 0.05). Dietary resveratrol significantly downregulated expression of Keap1 and upregulated expression of Nrf2 in duck (p < 0.05). Dietary resveratrol suppressed the TLR4/NF-κB signalling pathway and the expression of its downstream genes including IKK, TXNIP, NLRP3, Caspase-1, IL-6 and IL-18. Meanwhile, the levels of inflammatory cytokines (IL-6, IL-18 and TNF-α) showed a linearly decrease (p < 0.01) with increasing dietary resveratrol level. These results demonstrated that resveratrol alleviated the LPS-induced acute ileitis of duck through Nrf2 and NF-κB signalling pathways, and the dietary resveratrol of 500 mg/kg is more efficiently.

Anti-inflammatory naphthoates and anthraquinones from the roots of Morinda officinalis

Morinda (Morinda officinalis) is widely consumed as a health-care herb in Asia and reported to possess various biological activities. In this study, anti-inflammatory phytochemicals were investigated and two pairs of new methyl-2-naphthoate enantiomers (1a/1b, 2a/2b), one new anthraquinone (3), three new natural unknown anthraquinones (5-6, 23), and eighteen known anthraquinones were isolated and elucidated from the roots of morinda. Anti-inflammatory activities of the isolated compounds were assessed in lipopolysaccharide-stimulated RAW 264.7 macrophages. Compounds 2b and 19 significantly inhibited the production of NO with IC₅₀ values of 34.32 ± 4.87 and 17.17 ± 4.13 μM (indomethacin, IC₅₀ 26.71 ± 6.32 μM), and they were further corroborated via immunoblotting, quantitative real-time PCR and immunofluorescence staining assays. They could dose-dependent suppress lipopolysaccharide-stimulated pro-inflammatory factors (COX-2 and iNOS) production and block nuclear translocation of NF-κB. The results implied that reasonable consumption of morinda may be beneficial for preventing and reducing the occurrence of inflammatory-associated diseases.