Screening potential anti-osteoarthritis compounds using molecular docking based on MAPK and NFκB pathways and validating their anti-osteoarthritis effect

Abstract

Osteoarthritis is an extremely common disease. However, it lacks effective nonsurgical treatments. Molecular docking has been widely used in drug discovery. However, no studies focus on screening anti-osteoarthritis compounds using molecular docking. This study aimed to screen potential anti-osteoarthritis compounds using molecular docking and validate their anti-osteoarthritis effect. Molecular dockings between 51 compounds inhibiting the MAPK and NFκB pathways but have not been used to treat osteoarthritis and 5 core human proteins in the MAPK and NFκB pathways were performed. Corilagin, Apigetrin, Protopine, 5-methoxyflavone, and 7,3',4'-trihydroxyisoflavone were selected. The drug-likeness, pharmacokinetics, bioactivity, and toxicity of the selected compounds were analyzed. The cytotoxicity and anti-osteoarthritis effect of the selected compounds were tested on mouse chondrocytes. This study found that molecular docking based on the MAPK and NFκB pathways can be used to screen potential anti-osteoarthritis compounds, providing a perspective on drug discovery through pathway-based screening. ERK2, JNK2, and p38 showed similar binding sites commonly interacting with the compounds. The theoretical drug-likeness, pharmacokinetics, bioactivity, and toxicity were largely consistent with the empirical cytotoxicity and anti-osteoarthritis effect. Additionally, Protopine, 5-methoxyflavone, and 7,3',4'-trihydroxyisoflavone showed strong anti-osteoarthritis potential and can be considered for future studies to test their anti-osteoarthritis effect in animal models, explore molecular mechanisms, and improve their solubility.

Fig 1. The roles of the MAPK and NFκB pathways in the onset and progression of osteoarthritis.

Molecular docking is a powerful computational technique used to simulate the interaction between a compound and a protein to evaluate their binding potential. As a strong competitor to high-throughput omics, this technique has been widely used in drug discovery [10]. However, to our knowledge, no studies focused on screening anti-osteoarthritis compounds using molecular docking. This study aimed to screen potential anti-osteoarthritis compounds by docking with core human proteins in the MAPK and NFκB pathways, analyze their drug-likeness, pharmacokinetics, bioactivity, and toxicity, and test their cytotoxicity and anti-osteoarthritis effect on mouse chondrocytes.

Fig 2. Study design.

Fig 3. Distribution of phi and psi of residues.

A, B, and L indicate most favored regions. a, b, l, and p indicate additional allowed regions. ~ a, ~ b, ~ l, and ~ p indicate generously allowed regions. Triangles indicate glycine residues.

Fig 4. Bonding energies (kcal/mol) of molecular dockings between compounds and proteins.

Compounds were ranked from lowest to highest based on the first binding energy score formula.

Fig 5. Positional relationships between compounds and ERK2 and interactions between compounds and residues.

Fig 6. Positional relationships between compounds and JNK2 and interactions between compounds and residues.

Fig 7. Positional relationships between compounds and p38 and interactions between compounds and residues.

Fig 8. Positional relationships between compounds and p65 and interactions between compounds and residues.

Fig 9. Positional relationships between compounds and I

κBα and interactions between compounds and residues.

Fig 10. Interactions between compounds and residues.

The top 10 compounds ranked based on the second binding energy score formula are Sesamolin, Rutaecarpine, Corilagin, Apigetrin, Gamabufotalin, Protopine, Viaminate, 5-methoxyflavone, 7,3’,4’-Trihydroxyisoflavone, and Savinin (S6 Table).

Fig 11. Type II collagen and DAPI immunofluorescence staining images of mouse chondrocytes.

Fig 12. Cell viability of mouse chondrocytes at 24 h after treatment with compounds.

Fig 13. NO concentration in the mouse chondrocyte culture medium at 24 h after treatment with compounds.

“*” indicates P <  0.05. “**” indicates P <  0.01. “***” indicates P <  0.001. “****” indicates P <  0.0001.