Impact of Cilostazol Pharmacokinetics on the Development of Cardiovascular Side Effects in Patients with Cerebral Infarction

Genotype-guided dual antiplatelet therapy in cerebrovascular disease: assessing the risk and benefits for ethnic populations

INTRODUCTION

Cerebrovascular disease is a leading cause of morbidity and mortality in the world and antiplatelet therapy is a main pharmacologic means of secondary prevention. Clinical information has accumulated about benefit of dual antiplatelet therapy in certain clinical scenarios, genetic causes of antiplatelet resistance and its effect on clinical outcomes, and ethnic and geographic distributions of genetic polymorphisms.

AREAS COVERED

This review covers literature related to the pharmacogenomics of antiplatelet agents with a focus on ethnic variability, antiplatelet resistance, and dual antiplatelet therapy in cerebrovascular disease.

EXPERT OPINION

Selecting patients for dual antiplatelet therapy and specific agents require consideration of multiple factors. Ethnic factors should be considered in certain circumstances, but additional research is needed to determine the generalizability of the findings.

Adenosine diphosphate-induced aggregation is enhanced in platelets obtained from patients with thrombotic primary antiphospholipid syndrome (t-PAPS): Role of P2Y12 -cAMP signaling pathway

BACKGROUND

Thrombotic antiphospholipid syndrome (t-PAPS) is characterized by arterial, venous, or microvascular occlusions, which are explained, in part, by the presence of antiphospholipid (aPL) antibodies. Although there is much evidence indicating that isolated aPL antibodies increase the activity of platelets obtained from healthy volunteers, platelet function in t-PAPS has not been as widely studied.

OBJECTIVE

To evaluate platelet reactivity in t-PAPS patients.

METHODS

Platelet aggregation, protein expression, and cyclic nucleotide levels were carried out in platelet rich plasma (PRP) or washed platelets (WPs) obtained from t-PAPS or healthy volunteers.

RESULTS

ADP-induced aggregation was significantly higher in PRP obtained from t-PAPS than obtained from the control. The protein expression of P2Y12 receptor and Gs alpha was significantly higher and lower, respectively in WPs from t-PAPS patients. In PRP incubated with iloprost or sodium nitroprusside, the residual platelet reactivity induced by ADP was still higher in PRP from t-PAPS than from the control. Lower intracellular levels of cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) were observed in unstimulated PRP from t-PAPS patients. The protein expression of soluble guanylate cyclase subunits and phosphodiesterases types 3 and 5 did not differ. The antiplatelet activity of ticagrelor was similar between the groups and cilostazol significantly potentiated this response. Isolated aPL antibodies obtained from t-PAPS patients potentiated ADP-induced aggregation in healthy platelets but did not affect the inhibitory responses induced by iloprost or sodium nitroprusside.

CONCLUSIONS

The overexpression of P2Y12 receptor, accompanied by lower levels of cAMP and cGMP levels produced greater amplitude of ADP aggregation in platelets from t-PAPS patients.