Structural and functional integrity of endocrine pancreas post administration of Karwinskia humboldtiana fruit to Wistar rats: a possible therapeutic application for cancer of exocrine origin

Abstract

Aims. Pancreatic adenocarcinoma represents a therapeutic challenge due to the high toxicity of antineoplastic treatments and secondary effects of pancreatectomy. T-514, a toxin isolated from Karwinskia humboldtiana (Kh) has shown antineoplastic activity on cell lines. In acute intoxication with Kh, we reported apoptosis on the exocrine portion of pancreas. One of the mechanisms of antineoplastic agents is the induction of apoptosis, therefore our main objective was to evidence structural and functional integrity of the islets of Langerhans after the administration of Kh fruit in Wistar rats. Methods. TUNEL assay and immunolabelling against activated caspase-3 were used to detect apoptosis. Also, immunohistochemical tests were performed to search for glucagon and insulin. Serum amylase enzyme activity was also quantified as a molecular marker of pancreatic damage. Results. Evidence of toxicity on the exocrine portion, by positivity in the TUNEL assay and activated caspase-3, was found. On the contrary, the endocrine portion remained structurally and functionally intact, without apoptosis, and presenting positivity in the identification of glucagon and insulin. Conclusions. These results demonstrated that Kh fruit induces selective toxicity on the exocrine portion and establish a precedent to evaluate T-514 as a potential treatment against pancreatic adenocarcinoma without affecting the islets of Langerhans.