A Western Diet Modifies the Activation Profile of Circulating Platelets

Abstract

Background: While it is known that obesity increases the risk for cardiovascular disease (CVD), there has been no clear investigation into the effect an obesogenic diet exerts onto circulating platelets. As platelets are the critical actors in the formation of occlusive clots that manifest as a myocardial infarction or stroke, it is pertinent to establish any potential link between obesity and platelet activity. Methods: To examine the effect of a Western diet on baseline platelet activity, male C57BL6/J mice were fed either a control (10% fat, 7% sucrose, 0.3% salt Research Diets Inc. D12450J) or Western (40% fat, 30% sucrose, 8% salt Research Diets Inc. D06111701) diet ad libitum for 20 weeks beginning at the time of weaning. At 12, 16 and 20 weeks after beginning diet administration whole blood was collected via the retro-orbital sinus. Blood was used to generate platelet rich plasma (PRP) which was stimulated with collagen (20mg/ml) prior to staining for flow cytometry analysis. Flow cytometry staining utilized antibodies to recognize the platelet receptors GPIbα, P-Selectin and the activated form of integrin α IIb β 3 (JON/A). Additionally, body composition was likewise determined at these time points using Echo-MRI while bodyweight was measured weekly. Results: Western diet fed mice gained slightly more weight than control mice and had a higher percentage of body fat (measured by EchoMRI). Surprisingly, the two groups differed in GPIbα and activated α IIb β 3 expression on circulating platelets at all three observed time points. Specifically, platelets from control-fed mice displayed significantly higher GPIbα expression throughout the study while Western diet fed animals had higher levels of activated α IIb β 3 . There was no difference in platelet expression of P-Selectin between the groups at any time point. Conclusions: Platelet activation is not a binary process where platelets display a definitive “active” or “inactive” phenotype. Though terminal platelet activation elicits de-granulation and an increase in P-Selectin expression, the spectrum of platelet stimulation preceding this is marked by variable incidences of integrin activation and GPIbα shedding. Here we demonstrate proof of principle that dietary factors, such as the consumption of a Western diet, can facilitate early changes to the stimulation pattern of circulating platelets which is then maintained long-term. While the consequence of this altered platelet stimulation profile is unknown with regards to the pathways of hemostasis and thrombosis, further investigations of downstream signaling and amplification pathways are needed. Funding: Arkansas Children's Research Institute/Arkansas Bioscience Institute Postgraduate Fellowship: AWD-037176 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.