Reparixin (Repertaxin)

Reparixin is a non-competitive allosteric blocker of CXCR1 and CXCR2 receptor activation, which inhibits intracellular signal pathways without affecting receptor bindings. Reparixin potently and selectively inhibits a wide range of biological activities that are induced by CXCL8 such as leukocytes recruitment and functional inflammatory reactions. However, reparixin does not affect CXCR1/CXCR2 activation induced by other chemotactic factors, C5a, fMLP, CXCL12 or several other agonists of GPCRs. Reparixin can regulate the production of angiotensin II receptors, which may influence Ang II-induced hypertension^[1]. Reparixin specifically blocks CXCR1/2-mediated mouse and human neutrophil migration in vitro without affecting other receptors. Reparixin inhibits CXCL8-induced neutrophil activation through human CXCR1 and human CXCR2 and blocks phosphorylation of downstream signalling molecules. Reparixin prevents the increase of intracellular free calcium, elastase release and production of reactive oxygen intermediates, but leaves phagocytosis of Escherichia coli bacteria unaffected^[2].

HUVECs are pretreated without or with reparixin (1 μM) for 30 min. Cells were then treated with or without Ang II (100 nmol/l) or CXCL8 (100 ng/ml) for 2 h. After total RNA is isolated, real-time PCR was performed.

Reparixin, an inhibitor of CXCL8 receptor CXCR1 and CXCR2 activation, attenuates inflammatory responses in various injury models. Reparixin effectively decreases systolic blood pressure and increases the blood flow. The thoracic aorta wall thickness is significantly decreased in SHR-R (the reparixin-treated group) compared to SHR-N (normal saline-treated SHR)^[1]. (SHR: Spontaneously hypertensive rats)