Anti-inflammatory activity of Jefea gnaphalioides (a. gray), Astereaceae

Design, synthesis and biological evaluation of bakuchiol derivatives as multi-target agents for the treatment of Alzheimer's disease

The concept of multi-target-directed ligands offers fresh perspectives for the creation of brand-new Alzheimer's disease medications. To explore their potential as multi-targeted anti-Alzheimer's drugs, eighteen new bakuchiol derivatives were designed, synthesized, and evaluated. The structures of the new compounds were elucidated by IR, NMR, and HRMS. Eighteen compounds were assayed for acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in vitro using Ellman's method. It was shown that most of the compounds inhibited AChE and BuChE to varying degrees, but the inhibitory effect on AChE was relatively strong, with fourteen compounds showing inhibition of >50% at the concentration of 200 μM. Among them, compound 3g (IC50 = 32.07 ± 2.00 μM) and compound 3n (IC50 = 34.78 ± 0.34 μM) showed potent AChE inhibitory activities. Molecular docking studies and molecular dynamics simulation showed that compound 3g interacts with key amino acids at the catalytically active site (CAS) and peripheral anionic site (PAS) of acetylcholinesterase and binds stably to acetylcholinesterase. On the other hand, compounds 3n and 3q significantly reduced the pro-inflammatory cytokines TNF-α and IL-6 released from LPS-induced RAW 264.7 macrophages. Compound 3n possessed both anti-acetylcholinesterase activity and anti-inflammatory properties. Therefore, an in-depth study of compound 3n is expected to be a multi-targeted anti-AD drug.

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.

Extract of Pinus densiflora needles suppresses acute inflammation by regulating inflammatory mediators in RAW264.7 macrophages and mice

CONTEXT

Pinus densiflora Siebold & Zucc. (Pinaceae) needle extracts ameliorate oxidative stress, but research into their anti-inflammatory effects is limited.

OBJECTIVE

To investigate antioxidant and anti-inflammatory effects of a Pinus densiflora needles (PINE) ethanol extract in vitro and in vivo.

MATERIALS AND METHODS

We measured levels of reactive oxygen species (ROS), superoxide dismutase (SOD) and inflammatory mediators in lipopolysaccharide (LPS)-stimulated RAW264.7 cells at various PINE concentrations (25, 50 and 100 μg/mL; but 6.25, 12.5 and 25 μg/mL for interleukin-1β and prostaglandin E₂ (PGE₂)). Thirty ICR mice were randomized to six groups: vehicle, control, PINE pre-treatment (0.1, 0.3 and 1 mg/left ear for 10 min followed by arachidonic acid treatment for 30 min) and dexamethasone. The posttreatment ear thickness and myeloperoxidase (MPO) activity were measured.

RESULTS

PINE 100 μg/mL significantly decreased ROS (IC₅₀, 70.93 μg/mL, p < 0.01), SOD (IC₅₀, 30.99 μg/mL, p < 0.05), malondialdehyde (p < 0.01), nitric oxide (NO) (IC₅₀, 27.44 μg/mL, p < 0.01) and tumour necrosis factor-alpha (p < 0.05) levels. Interleukin-1β (p < 0.05) and PGE₂ (p < 0.01) release decreased significantly with 25 μg/mL PINE. PINE 1 mg/ear inhibited LPS-stimulated expression of cyclooxygenase-2 and inducible NO synthase in RAW264.7 macrophages and significantly inhibited ear oedema (36.73-15.04% compared to the control, p < 0.01) and MPO activity (167.94-105.59%, p < 0.05).

DISCUSSION AND CONCLUSIONS

PINE exerts antioxidant and anti-inflammatory effects by inhibiting the production of inflammatory mediators. Identified flavonoids such as taxifolin and quercetin glucoside can be attributed to effect of PINE.