Increased Cardiovascular Risk Associated with Chemical Sensitivity to Perfluoro-Octanoic Acid: Role of Impaired Platelet Aggregation

Perfluoro\u2013alkyl substances (PFAS), particularly perfluoro\u2013octanoic acid (PFOA), are persisting environmental chemicals showing bioaccumulation in human tissues. Recently, exposure to PFAS has been associated with increased prevalence of cardiovascular diseases (CVDs). However, a causal role of PFAS in atherosclerosis pathogenesis is under-investigated. Here, we investigated the effect of PFOA exposure on platelets\u2019 function, a key player in atherosclerosis process. PFOA accumulation in platelets was evaluated by liquid chromatography-mass spectrometry. Changes in platelets\u2019 membrane fluidity and activation after dose-dependent exposure to PFOA were evaluated by merocyanine 540 (MC540) and anti P-Selectin immune staining at flow cytometry, respectively. Intracellular calcium trafficking was analyzed with Fluo4M probe, time-lapse live imaging. Platelets\u2019 aggregation state was also evaluated with Multiplate\uae aggregometry analyzer in 48 male subjects living in a specific area of the Veneto region with high PFAS environmental pollution, and compared with 30 low-exposure control subjects. Platelets\u2019 membrane was the major target of PFOA, whose dose-dependent accumulation was associated in turn with increased membrane fluidity, as expected by a computational model; increased activation at resting condition; and both calcium uptake and aggregation upon activation. Finally, exposed subjects had higher serum and platelets levels of PFOA, together with increased aggregation parameters at Multiplate\uae, compared with controls. These data help to explain the emerging association between PFAS exposure and CVD

E2F1 copy number variations contribute to spermatogenic impairment and cryptorchidism by increasing susceptibility to heat stress

Background: Copy number variations (CNVs) play an important role in the onset of several diseases, and recently research focused on the relationship between these structural variants and diseases of the reproductive tract, including male infertility and cryptorchidism. Objectives: To evaluate the contribution of copy number variations of E2F1 gene to idiopathic male infertility and the factors influencing expression of this gene. Materials and Methods: We performed a retrospective study on 540 subjects recruited from September 2014 to February 2015. TaqMan CNV assay was used to analyze E2F1 CNV. Real-time PCR was used to assess E2F1 and HSP70 expression level in heat stressed and transfected cells with three E2F1 copies. Results: We found a significant difference in the frequency of altered E2F1 copies in patients (12/343, 3.5%) compared with controls (0/197) (p\ua0=\ua00.005). Six patients with E2F1 CNV had history of cryptorchidism, but the prevalence between men with idiopathic infertility (6/243, 2.5%) and infertile men with history of cryptorchidism (6/100, 6.0%) was not statistically different (p\ua0=\ua00.1). E2F1 expression increased under heat stress conditions, especially in cells carrying more copies of gene and this was associated with increased expression of HSP70. Discussion: Our data suggest that an abnormal E2F1 expression caused by multiple copies of E2F1 gene predisposes to the onset of infertility and that the risk further increases if subjects with altered E2F1 copies have stressful conditions, such as heat stress or history of cryptorchidism. Conclusion: This study shows a link between E2F1 CNV and male infertility, suggesting that the increased risk of spermatogenic impairment associated with higher E2F1 copies might be due to higher susceptibility to stressful conditions