*Purpose: : The biological effects of hepatocyte growth factor/scatter factor (HGF) and its mimetics are mediated by a signal cascade initiated by binding of HGF to its tyrosine kinase receptor, c-Met, which is constitutively expressed at low levels on the epithelial cells of most tissues and unregulated in the setting of injury Interaction of HGF and c-Met causes activation of cellular pathways that results in cellular proliferation. We examined the ability of ANG-3777 to phosphorylate c-Met in vivo in rat hepatocytes, and rat kidney in a model of renal ischemia and reperfusion.

*Methods: For the hepatocyte study, adult male Sprague-Dawley (SD) rats were treated with 40 mg/kg ANG-3777 or vehicle via intraperitoneal injection. Animals were sacrificed at 0‑minute, 30‑minute, 1-hour, and 2-hour time points and perfused with phosphate-buffered saline for 5 minutes. The liver samples were collected, normalized by weight, and homogenized. The sample aliquots were diluted with radioimmunoprecipitation assay buffer and analyzed by Western blot using rabbit phosphorylated-c-Met antibody. For the model of renal ischemia and reperfusion, adult male SD rats were subjected to 60-minute normothermic unilateral ischemia followed by 24-hour reperfusion; ANG-3777 (2 mg/kg, intravenously) or vehicle was administered at the onset of reperfusion and again at 18 hours of reperfusion. Animals were sacrificed at 18, 20, or 24 hours of reperfusion, and total c-Met and phosphorylated c-Met in kidney extracts were assessed by Western blot analysis.

*Results: For in vivo liver cells, ANG-3777 phosphorylated c-Met with peak intensity at 1-hour post-injection (Figure 1A). Ischemia-reperfusion injury provoked a time-dependent increase in kidney total c-Met. In rat kidney cell, 60 minutes of ischemia followed by 24 hr reperfusion provoked a time-dependent increase in kidney total c-Met in both vehicle and ANG-3777-treated rats. Treatment with ANG-3777 (2 mg/kg, i.v.) resulted in a robust increase in phosphorylated c-Met levels (Figure 1B).

*Conclusions: ANG-3777 induces phosphorylation of c-Met in normal rat liver in a time‑dependent manner, and in a rat renal ischemia reperfusion model, ANG-3777 induced a robust increase in phosphorylated c-Met at 24 hours post-reperfusion.

« Back to 2020 American Transplant Congress