Safflower yellow alleviates osteoarthritis and prevents inflammation by inhibiting PGE2 release and regulating NF-κB/SIRT1/AMPK signaling pathways.

Abstract

BACKGROUND:

Safflower yellow (SY) is the main active ingredient of safflower, with various pharmacological effects such as anticoagulating, antioxidant, and anti-arthritis effects.

PURPOSE:

To investigate the anti-inflammatory and chondrocyte protecting role of SY, which subsequently leads to the inhibition of cartilage degradation.

METHODS:

Rat chondrocytes were stimulated with tumor necrosis factor α (TNF-α) with or without SY treatment. Following this, CCK-8 assay was performed to detect cytotoxicity. RT-qPCR, Western blotting, and immunofluorescence staining were used to detect the gene/protein expression of typical cartilage matrix genes and related inflammatory markers. Subsequently, EdU assay was used to evaluate cell proliferation. RNA sequencing, online target prediction, and molecular docking were performed to determine the possible molecular targets and pathways.

RESULTS:

The results showed that SY restored the TNF-α-induced up-regulation of IL-1β, PTGS2, and MMP-13 and down-regulation of COL2A1 and ACAN. Furthermore, it recovered cell proliferation by suppressing TNF-α. Gene expression profiles identified 717 differentially expressed genes (DEGs) in the cells cultured with or without SY under TNF-α stimulation. After pathway enrichment, PI3K-Akt, TNF, Cytokine-cytokine receptor interaction, NF-κB, NOD-like receptor, and Chemokine signaling pathways were notably selected to highlight NFKBIA, CCL5, CCL2, IL6, and TNF as potential targets in osteoarthritis (OA). SY inhibited TNF-α-induced activation of NF-κB and endoplasmic reticulum (ER) stress by promoting AMPK phosphorylation along with SIRT1 expression. Further, SY reduced MMP-13 expression and targeted COX-2 for decreasing PGE2 release. In addition, anterior cruciate ligament transection-induced OA was ameliorated by local administration of SY.

CONCLUSION:

These results demonstrate that SY protects chondrocytes and inhibits inflammation by regulating the NF-κB/SIRT1/AMPK pathways and ER stress, thus preventing cartilage degeneration in OA.

• Authors: Chunli Wang, Yan Gao, Zike Zhang, Qingjia Chi, Yanju Liu, Li Yang, Kang Xu
• Journal: Phytomedicine : international journal of phytotherapy and phytopharmacology (Phytomedicine) Vol. 78 Pg. 153305 (Nov 2020) ISSN: 1618-095X [Electronic] Germany
• PMID: 32871523 (Publication Type: Journal Article)
• Copyright: Copyright © 2020 Elsevier GmbH. All rights reserved.

Chemical References

• NF-kappa B
• safflower yellow
• Chalcone
• AMP-Activated Protein Kinases
• Matrix Metalloproteinase 13
• Mmp13 protein, rat
• Sirt1 protein, rat
• Sirtuin 1
• Dinoprostone

Topics

• AMP-Activated Protein Kinases (metabolism)
• Animals
• Chalcone (analogs & derivatives, chemistry, pharmacology)
• Chondrocytes (drug effects, metabolism)
• Dinoprostone (metabolism)
• Gene Expression Regulation (drug effects)
• Humans
• Matrix Metalloproteinase 13 (genetics)
• Molecular Docking Simulation
• NF-kappa B (metabolism)
• Osteoarthritis (drug therapy, metabolism, pathology)
• Phosphatidylinositol 3-Kinases (metabolism)
• Rats, Sprague-Dawley
• Signal Transduction (drug effects)
• Sirtuin 1 (metabolism)