Activation of the pentose phosphate pathway mitigates platelet storage lesions and improves platelet preservation quality

Abstract

Background

Platelet storage lesions (PSLs) impact platelet lifespan and transfusion quality. This study explores platelet storage metabolism for potential interventions.

Methods

Samples were collected on days 1, 3, and 5 for untargeted metabolomics analysis to identify metabolites that differ with storage time and potential metabolic pathways. The activities of glucose-6-phosphate dehydrogenase (G6PD) and cyclooxygenase-1 (COX-1) in platelets during storage were measured. Meanwhile, flow cytometry was used to assess changes in apoptosis and mitochondrial function of stored platelets treated with either a G6PD inhibitor, a G6PD activator, or a COX-1 inhibitor. Platelet aggregation was used to evaluate platelet function. Megakaryocyte/platelet-specific G6pd knockout mice were used to assess the role of G6PD in PSLs.

Results

The pentose phosphate pathway (PPP), arachidonic acid metabolism, and linoleic acid metabolism were enriched during storage. A total of 4832 platelet metabolites and 6468 plasma metabolites were identified, with 44 and 108 showing nominally significant changes respectively. An increase in G6PD activity was observed at the early stages. Inhibiting G6PD with G6PDi-1 damages mitochondria, increases phosphatidylserine externalization, and impairs platelet aggregation. Mouse G6pd^−/− platelets exhibited increased PSLs. Activation of G6PD with AG1 reduces mitochondrial reactive oxygen species (mtROS) and phosphatidylserine externalization while enhancing platelet aggregation. Additionally, although COX-1 activity in the arachidonic acid metabolism pathway increases at the early stage, its inhibition by the COX-1 inhibitor aspirin does not significantly alter PSL-related indicators.

Conclusion

The pentose phosphate pathway maintains platelet mitochondrial function via G6PD regulation, making G6PD a critical target for reducing PSLs.