Cotinine inhibits TLR4/NF-κB signaling pathway and improves deep vein thrombosis in rats

Area of Science:

• Biomedical Science
• Pharmacology
• Pathophysiology

Background:

• Deep vein thrombosis (DVT) is a significant health concern.
• Understanding the molecular mechanisms underlying DVT is crucial for developing effective treatments.
• Cotinine, a metabolite of nicotine, has been implicated in various physiological processes.

Purpose of the Study:

• To investigate the regulatory mechanisms of cotinine on DVT in a rat model.
• To explore the role of the toll-like receptor 4/nuclear factor κ binding (TLR-4/NF-κB) pathway in cotinine-induced DVT.
• To analyze the impact of cotinine on inflammatory markers and coagulation factors in DVT.

Main Methods:

• Establishment of a DVT rat model.
• Administration of cotinine at a dose of 10 μg/kg.
• Analysis of thromboxane B2 (TXB2), 6-keto-PGF1α, plasminogen activator inhibitor (PAI), and tissue plasminogen activator (t-PA) levels.
• Assessment of TLR-4 and NF-κB (including p65) mRNA and protein expression using RT-PCR and Western blot.
• Histopathological examination of venous tissues using Hematoxylin-Eosin (HE) staining.

Main Results:

• Cotinine administration significantly increased TXB2, PAI, IL-6, TNF-α, TLR-4, and NF-κB levels.
• Cotinine significantly decreased 6-keto-PGF1α and t-PA levels in DVT rats.
• These changes were associated with aggravated thrombus formation and inflammation in the venous tissues.
• The model + cotinine group exhibited more pronounced alterations compared to the model group.

Conclusions:

• Cotinine exacerbates thrombus formation and inflammation in rats with DVT.
• The mechanism underlying cotinine's effect involves the activation of the TLR-4/NF-κB inflammatory signaling pathway.
• These findings suggest that cotinine may play a detrimental role in the pathogenesis of DVT.