Anti-Inflammatory Activity of Essential Oil from Zingiber ottensii Valeton in Animal Models

Essential Oil of Matricaria chamomilla Alleviate Psoriatic-Like Skin Inflammation by Inhibiting PI3K/Akt/mTOR and p38MAPK Signaling Pathway

Background

The traditional Matricaria chamomilla L. has been used to treat dermatitis for thousands of years. Due to emerging trends in alternative medicine, patients prefer natural remedies to relieve their symptoms. Therefore, finding safe and effective plant medicines for topical applications on the skin is an important treatment strategy for dermatologists. German chamomile (Matricaria chamomilla L.) from the Compositae family is a famous medicinal plant, often known as the "star of medicinal species."However, the function of Matricaria chamomilla essential oil on skin inflammation has not been thoroughly examined in earlier research.

Methods

GC-MS analyzed the components of MCEO, and this study explored the anti-inflammation effects of MCEO on psoriasis with network pharmacological pathway prediction. Following this, we used clinical samples of psoriasis patients to confirm the secretory characteristic of relative inflammatory markers. The therapeutic effect of MCEO on skin inflammation was detected by examination of human keratinocytes HaCaT. At the same time, we prepared imiquimod-induced psoriatic-like skin inflammation in mice to investigate thoroughly the potential inhibition functions of MCEO on psoriatic skin injury and inflammation.

Results

MCEO significantly reduced interleukin-22/tumor necrosis factor α/lipopolysaccharide-stimulated elevation of HaCaT cell inflammation, which was correlated with downregulating PI3K/Akt/mTOR and p38MAPK pathways activation mediated by MCEO in HaCaT cells treated with IL-22/TNF-α/LPS. Skin inflammation was evaluated based on the PASI score, HE staining, and relative inflammatory cytokine levels. The results showed that MCEO could significantly contribute to inflammatory skin disease treatment.

Conclusion

MCEO inhibited inflammation in HaCaT keratinocytes induced by IL-22/TNF-α/LPS, the potential mechanisms associated with inhibiting excessive activation and crosstalk between PI3K/Akt/mTOR and p38MAPK pathways. MCEO ameliorated skin injury in IMQ-induced psoriatic-like skin inflammation of mice by downregulating the levels of inflammatory cytokines but not IL-17A. Thus, anti-inflammatory plant drugs with different targets with combined applications were a potential therapeutic strategy in psoriasis.

Exploring molecular docking with MM-GBSA and molecular dynamics simulation to predict potent inhibitors of cyclooxygenase (COX-2) enzyme from terpenoid-based active principles of Zingiber species

Cyclooxygenase 2 (COX-2), the key enzyme involved in prostaglandin (PGs) production, is known to take part in inflammatory and immune responses. Though COX-2 inhibitors are therapeutically effective anti-inflammatory drugs, they deficit anti-thrombotic activity thus leading to increased cardiovascular diseases. Therefore, COX-2 inhibitors with improved therapeutic efficacy and tolerance are still needed. In recent years, traditional medicine systems have paid attention to the essential oil of genus Zingiber, particularly for the treatment of various inflammatory illnesses, with lesser side effects. Thus, the present study aims to explore the anti-inflammatory activity of Zingiber essential oil through computational-biology approaches. In this regard, virtual screening, molecular docking, and simulations were carried out on 53 compounds derived from the essential oil of Zingiber species in order to provide mechanistic insights into COX-2 inhibition and identify the most actively potent anti-inflammatory compounds. Among all the docked ligands, epi-cubenol, δ-cadinene, γ-eudesmol, cubenol, and α-terpineol were found to be powerful bioactive compounds with an increased binding affinity towards COX-2 along with favorable physiochemical properties. Additionally, MD simulation in DPPC lipid bilayers was studied to examine the intrinsic dynamics and adaptability of the chosen ligands and COX-2-complexes. The findings showed that the selected five components interacted steadily with the COX-2 active site residues throughout the simulation via different bondings. The integrative-computational approach showed that the identified natural compounds may be taken into further consideration for potential in vitro and in vivo evaluation as COX-2 inhibitors, which would lead to the development of more potent and efficient anti-inflammatory drugs.Communicated by Ramaswamy H. Sarma.

Akebia Saponin D Inhibits the Inflammatory Reaction by Inhibiting the IL-6-STAT3-DNMT3b Axis and Activating the Nrf2 Pathway

Akebia saponin D (ASD) is derived from the Dipsacus asper Wall. ex Henry, which is a traditional Chinese medicine commonly used to treat rheumatic arthritis (RA). However, the in-depth mechanism of the anti-inflammatory effect of ASD is still unclear. This study aimed to preliminarily explore the anti-inflammatory effect of ASD and the underlying mechanisms from the perspective of DNA methylation and inflammation-related pathways. We found that ASD significantly reduced the production of multiple inflammatory mediators, including nitric oxide (NO) and prostaglandin E₂ (PGE₂), in LPS-induced RAW264.7 cells. The expression of DNA methyltransferase (DNMT) 3b and inducible nitric oxide synthase (iNOS) was also obviously inhibited by the ASD treatment. The protein and mRNA levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were also significantly inhibited by ASD. ASD inhibited the macrophage M1 phenotype, inhibited the high level of DNMT3b, and downregulated the signal transducer and activator of the transcription 3 (STAT3) pathway to exert its anti-inflammatory activity. Furthermore, DNMT3b siRNA and Nrf2 siRNA significantly promoted the anti-inflammatory effect of ASD. Our study demonstrates for the first time that ASD inhibits the IL-6-STAT3-DNMT3b axis and activates the nuclear factor-E2-related factor 2 (Nrf2) signaling pathway to achieve its inhibitory effect on inflammatory reactions.