SLAMF8 Promotes Atherosclerosis by Activating the TLR4 Signaling Pathway in Rheumatoid Arthritis.

Area of Science:

• Immunology
• Cardiovascular Biology
• Molecular Medicine

Background:

• Rheumatoid arthritis (RA) significantly accelerates atherosclerosis (AS) plaque development.
• Early-stage RA patients exhibit a high prevalence of AS, necessitating research into underlying mechanisms.
• Understanding the molecular drivers of AS in RA is crucial for improved patient management.

Purpose of the Study:

• To identify key molecular mechanisms accelerating AS in RA patients.
• To investigate the role of the candidate hub gene SLAMF8 in AS pathogenesis within the context of RA.
• To explore SLAMF8's potential as a therapeutic target for AS in RA.

Main Methods:

• Gene expression data for RA and AS were analyzed using the Gene Expression Omnibus (GEO) database.
• SLAM family member 8 (SLAMF8) was identified as a key candidate hub gene through bioinformatic analysis.
• In vitro studies involved differentiating U937 cells into macrophages and foam cells, followed by SLAMF8 knockdown using siRNA, western blot, and RT-qPCR.

Main Results:

• SLAMF8 was identified as a crucial gene involved in AS development in RA.
• SLAMF8, TLR4, TNF-α, and IL-6 were significantly expressed in foam cells compared to macrophages.
• SLAMF8 knockdown reduced TLR4, TNF-α, and IL-6 protein levels, attenuating inflammation and apoptosis in foam cells via TLR4 inhibition.

Conclusions:

• SLAMF8 promotes AS in RA by inducing foam cell inflammation and apoptosis through TLR4 signaling.
• SLAMF8 represents a potential therapeutic target for mitigating AS severity in RA patients.
• Targeting SLAMF8 could offer a novel approach to managing cardiovascular complications in rheumatoid arthritis.