👤 Manuel Salzmann

Apolipoprotein C3 (apoC3) circulates primarily on triglyceride-rich lipoproteins and promotes atherosclerosis by fostering lipidemia and inflammation. Thus, apoC3 represents an important cardiovascular risk factor and is associated with cardiovascular events and mortality. Due to their dual nature as hemostatic and immunomodulatory effector cells, platelets play an important role in the development and progression of atherosclerosis and are responsible for thrombotic/thromboembolic events upon plaque rupture. We aimed to elucidate the impact of apoC3 on prothrombotic platelet functions. Platelets were isolated from healthy volunteers and the effect of apoC3 on their activation and aggregation was assessed by flow cytometry, ELISA, and light transmission and multiple electrode aggregometry. Platelet spreading and cytoskeletal remodeling were examined by immunofluorescence microscopy. In vivo relevance was confirmed in a murine model of FeCl ApoC3 strongly reduced platelet aggregation independently of the presence of plasma or other blood cells and impaired both α We identified apoC3 as lipoprotein-derived inhibitor of prothrombotic platelet functions, mediating antiaggregatory effects, likely via modulating AKT and VASP signaling and interfering with actin cytoskeleton remodeling to impair lamellipodia formation. Thus, apoC3 may counterbalance its proatherogenic properties on lipid metabolism and inflammation by dampening thrombotic risk in hyperlipidemia. Show less

Phosphoinositide-3-kinase, class III (PIK3C3) is a member of the phosphoinosite-3-kinases family, involved in cell signaling, membrane trafficking, and neurodevelopment. Previous studies have indeed shown an association between PIK3C3 gene variants and both bipolar disorder (BD) and schizophrenia (SZ). Brain-derived neurotrophic factor (BDNF) is a neurodevelopmental factor, which can regulate the PI3K signaling pathway. Associations have been reported between BDNF gene polymorphisms and affective and psychotic disorders. The aim of the present study was to replicate an association between PIK3C3 and BDNF gene variants in SZ and BD and a putative epistasis between the two genes. Patients meeting the DSM-IV criteria of BD and SZ were included in this study (98 BD and 79 SZ) as well as 158 healthy controls. Blood DNA was extracted and genotyping was performed either by the polymerase chain reaction (PCR) technique followed by enzymatic digestion or by the high-resolution melt (HRM) method. Genotype and haplotype association was assessed with the UNPHASED statistical program.The results showed one nominal association with BD (P < 0.02) and two risk haplotypes in both SZ (P < 0.001) and BP (P < 0.0005), which survived multiple testing correction. A modest interaction between a BDNF variant and PI3KC3 polymorphism was observed (P < 0.04).These preliminary results confirm the genetic association of PI3K gene variants with both SZ and BD, and support the hypothesis that SZ and BD share a genetic background. Show less