Platelet-Derived Drug Targets and Biomarkers of Ischemic Stroke-The First Dynamic Human LC-MS Proteomic Study

Promising therapeutic targets for ischemic stroke identified from plasma and cerebrospinal fluid proteomes: a multicenter Mendelian randomization study

BACKGROUND

Ischemic stroke (IS) is more common every year, the condition is serious, and have a poor prognosis. New, efficient, and safe therapeutic targets are desperately needed as early treatment especially prevention and reperfusion is the key to lowering the occurrence of poorer prognosis. Generally circulating proteins are attractive therapeutic targets, this study aims to identify potential pharmacological targets among plasma and cerebrospinal fluid (CSF) proteins for the prevention and treatment of IS using a multicenter Mendelian randomization (MR) approach.

METHODS

First, the genetic instruments of 734 plasma and 151 CSF proteins were assessed for causative connections with IS from MEGASTROKE consortium by MR to identify prospective therapeutic targets. Then, for additional validation, plasma proteins from the deCODE consortium and the Fenland consortium, as well as IS GWAS data from the FinnGen cohort, the ISGC consortium and UK biobank, were employed. A thorough evaluation of the aforementioned possible pharmacological targets was carried out using meta-analysis. The robustness of MR results was then confirmed through sensitivity analysis using several techniques, such as bidirectional MR analysis, Steiger filtering, and Bayesian colocalization. Finally, methods like Protein-Protein Interaction (PPI) Networking were utilized to investigate the relationship between putative drug targets and therapeutic agents.

RESULTS

The authors discovered three proteins that may function as promising therapeutic targets for IS and meet the Bonferroni correction ( P <0.05/885=5.65×10 -5 ). Prekallikrein (OR=0.41, 95% CI: 0.27-0.63, P =3.61×10 -5 ), a protein found in CSF, has a 10-fold protective impact in IS, while the plasma proteins SWAP70 (OR=0.85, 95% CI: 0.80-0.91, P =1.64×10 -6 ) and MMP-12 (OR=0.92, 95% CI: 0.89-0.95, P =4.49×10 -6 ) of each SD play a protective role in IS. Prekallikrein, MMP-12, SWAP70 was replicated in the FinnGen cohort and ISGC database. MMP-12 (OR=0.93, 95% CI: 0.91-0.94, P <0.001), SWAP70 (OR=0.92, 95% CI: 0.90-0.94, P <0.001), and prekallikrein (OR=0.53, 95% CI: 0.33-0.72, P <0.001) may all be viable targets for IS, according to the combined meta-analysis results. Additionally, no evidence of reverse causality was identified, and Bayesian colocalization revealed MMP-12 (PPH 4 =0.995), SWAP70 (PPH 4 =0.987), and prekallikrein (PPH 4 =0.894) shared the same variant with IS, supporting the robustness of the aforementioned causation. Prekallikrein and MMP-12 were associated with the target protein of the current treatment of IS. Among them, Lanadelumab, a new drug whose target protein is a prekallikrein, may be a promising new drug for the treatment of IS.

CONCLUSION

The prekallikrein, MMP-12, and SWAP70 are causally associated with the risk of IS. Moreover, MMP-12 and prekallikrein may be treated as promising therapeutic targets for medical intervention of IS.

Proteomic advance of ischemic stroke: preclinical, clinical, and intervention

Ischemic stroke (IS) is the most common type of stroke and is characterized by high rates of mortality and long-term injury. The prediction and early diagnosis of IS are therefore crucial for optimal clinical intervention. Proteomics has provided important techniques for exploring protein markers associated with IS, but there has been no systematic evaluation and review of research that has used these techniques. Here, we review the differential proteins that have been found in cell- and animal- based studies and clinical trials of IS in the past 10 years; determine the key pathological proteins that have been identified in clinical trials; summarize the target proteins affected by interventions aimed at treating IS, with a focus on traditional Chinese medicine treatments. Overall, we clarify findings and problems that have been identified in recent proteomics research on IS and provide suggestions for improvements in this area. We also suggest areas that could be explored for determining the pathogenesis and developing interventions for IS.

Protocols for the Isolation of Platelets for Research and Contrast to Production of Platelet Concentrates for Transfusion

Platelets are specialized cellular elements of blood and play a central role in maintaining normal hemostasis, wound healing, and host defense but also are implicated in pathologic processes of thrombosis, inflammation, and tumor progression and dissemination. Transfusion of platelet concentrates is an important treatment for thrombocytopenia (low platelet count) due to disease or significant blood loss, with the goal being to prevent bleeding or to arrest active bleeding. In blood circulation, platelets are in a resting state; however, when triggered by a stimulus, such as blood vessel injury, become activated (also termed procoagulant). Platelet activation is the basis of their biological function to arrest active bleeding, comprising a complex interplay of morphological phenotype/shape change, adhesion, expression of signaling molecules, and release of bioactive factors, including extracellular vesicles/microparticles. Advances in high-throughput mRNA and protein profiling techniques have brought new understanding of platelet biological functions, including identification of novel platelet proteins and secreted molecules, analysis of functional changes between normal and pathologic states, and determining the effects of processing and storage on platelet concentrates for transfusion. However, because platelets are very easily activated, it is important to understand the different in vitro methods for platelet isolation commonly used and how they differ from the perspective for use as research samples in clinical chemistry. Two simple methods are described here for the preparation of research-scale platelet samples from human whole blood, and detailed notes are provided about the methods used for the preparation of platelet concentrates for transfusion.

Smoking Affects the Post-Stroke Inflammatory Response of Lipid Mediators in a Gender-Related Manner

The main goal of our study was to determine the effect of cigarette smoking on selected derivatives of arachidonic acid, linoleic acid, DHA, and EPA, which may be markers of post-stroke inflammation. The eicosanoid profile was compared in both smoking and non-smoking patients, without division and with division into gender. In the group of non-smokers, we observed higher levels of the linolenic acid derivative (LA) 9S HODE (p ≤ 0.05) than in smokers. However, after dividing the results by sex, it turned out that the level of this derivative was higher in non-smoking women compared to smoking women (p ≤ 0.01) and did not differentiate the group of men. Similarly, the level of the arachidonic acid metabolite LTX A4 (p ≤ 0.05) differed only in the group of women. In this group, we also observed a decreased level of 15S HETE in smoking women, but it was statistically insignificant (p ≤ 0.08). On the other hand, the level of this derivative was statistically significantly higher in the group of non-smoking women compared to male non-smokers. The group of men was differentiated by two compounds: TXB2 and NPD1. Male smokers had an almost two-fold elevation of TXB2 (p ≤ 0.01) compared with non-smokers, and in this group, we also observed an increased level of NPD1 compared with male non-smokers. On the other hand, when comparing female non-smokers and male non-smokers, in addition to the difference in 15S HETE levels, we also observed elevated levels of TXB2 in the group of non-smokers. We also analyzed a number of statistically significant correlations between the analyzed groups. Generally, men and women smokers showed a much smaller amount of statistically significant correlations than non-smokers. We believe that this is related to the varying degrees of inflammation associated with acute ischemic stroke and post-stroke response. On the one hand, tobacco smoke inhibits the activity of enzymes responsible for the conversion of fatty acids, but on the other hand, it can cause the failure of the inflammatory system, which is also the body's defense mechanism. Smoking cigarettes is a factor that increases oxidative stress even before the occurrence of a stroke incident, and at the same time accelerates it and inhibits post-stroke repair mechanisms. This study highlights the effect of smoking on inflammation in both genders mediated by lipid mediators, which makes smoking cessation undeniable.