Reduced Annexin A1 Expression Associates with Disease Severity and Inflammation in Multiple Sclerosis Patients

Chronic neuroinflammation is a key pathological hallmark of multiple sclerosis (MS) that suggests that resolution of inflammation by specialized proresolving molecules is dysregulated in the disease. Annexin A1 (ANXA1) is a protein induced by glucocorticoids that facilitates resolution of inflammation through several mechanisms that include an inhibition of leukocyte recruitment and activation. In this study, we investigated the ability of ANXA1 to influence T cell effector function in relapsing/remitting MS (RRMS), an autoimmune disease sustained by proinflammatory Th1/Th17 cells. Circulating expression levels of ANXA1 in naive-to-treatment RRMS subjects inversely correlated with disease score and progression. At the cellular level, there was an impaired ANXA1 production by CD4⁺CD25^- conventional T and CD4⁺RORγt⁺ T (Th17) cells from RRMS subjects that associated with an increased migratory capacity in an in vitro model of blood brain barrier. Mechanistically, ANXA1 impaired monocyte maturation secondarily to STAT3 hyperactivation and potently reduced T cell activation, proliferation, and glycolysis. Together, these findings identify impaired disease resolution pathways in RRMS caused by dysregulated ANXA1 expression that could represent new potential therapeutic targets in RRMS.

Caffeine stimulates in vivo platelet reactivity

The effect of coffee drinking on platelet reactivity was studied in 12 healthy subjects. Plasma beta-thromboglobulin concentration was determined before and one hour after administration of 100 mg of caffeine, corresponding to one cup of coffee. Mean values were 47.0 +/- 19.3 and 179.3 +/- 85.5 ng/ml before and after caffeine administration respectively. The increase, 298 +/- 150%, is highly significant (p less than 0.001).

Prevention of platelet hyperaggregation during coronary angiography

The authors previously reported an increase in platelet aggregration in the days after coronary angiography, accompanied at times by worrying cardiovascular disorders (ventricular fibrillation in one case, death in two others). In the present study, ten patients received a platelet antiaggregating drug (ticlopidin) 5 days before their coronary angiography. No significant changes were detected in the test for circulating platelet aggregates (CPA test) in these patients.