Increased tissue factor activity in monocytes from obese young adults

Area of Science:

• Biochemistry
• Immunology
• Hematology

Background:

• The link between inflammation, obesity, and tissue factor (TF) initiation of clotting is unclear.
• Obesity is associated with chronic inflammation and an increased risk of thrombotic events.
• Understanding TF regulation in obesity is crucial for managing cardiovascular risks.

Purpose of the Study:

• To investigate if peripheral blood mononuclear cell (PBMC) TF procoagulant activity (PCA) is elevated in obese subjects.
• To examine the impact of obesity-related proteins (leptin, resistin, SAA) on PBMC TF-PCA.
• To explore the relationship between basal PBMC TF-PCA and inflammatory markers in obesity.

Main Methods:

• Compared basal and lipopolysaccharide (LPS)- or serum amyloid A (SAA)-stimulated PBMC TF-PCA in 12 obese and 12 lean individuals.
• Assessed the effect of leptin and resistin on PBMC TF-PCA in lean subjects.
• Measured TF-PCA using a 1-stage plasma recalcification assay and correlated it with serum hs-CRP, insulin, and SAA levels.

Main Results:

• Basal PBMC TF-PCA was significantly higher in obese individuals compared to lean controls (P=0.01).
• TF-PCA levels were similar between groups after stimulation with SAA or LPS.
• Unstimulated TF-PCA correlated with serum high-sensitivity C-reactive protein (hs-CRP) and insulin levels.

Conclusions:

• Basal PBMC TF-PCA is elevated in obesity and associated with systemic inflammation (hs-CRP).
• Obesity-related proteins SAA, leptin, and resistin do not appear to be major drivers of increased PBMC TF-PCA.
• Further research is needed to elucidate the precise mechanisms linking obesity, inflammation, and thrombosis risk.