Dillapiole as Antileishmanial Agent: Discovery, Cytotoxic Activity and Preliminary SAR Studies of Dillapiole Analogues

In this paper, the isolation of dillapiole (1) from Piper aduncum was reported as well as the semi-synthesis of two phenylpropanoid derivatives [di-hydrodillapiole (2), isodillapiole (3)], via reduction and isomerization reactions. Also, the compounds' molecular properties (structural, electronic, hydrophobic, and steric) were calculated and investigated to establish some preliminary structureactivity relationships (SAR). Compounds were evaluated for in vitro antileishmanial activity and cytotoxic effects on fibroblast cells. Compound 1 presented inhibitory activity against Leishmania amazonensis (IC50?=?69.3 mu M) and Leishmania brasiliensis (IC50?=?59.4 mu M) and induced cytotoxic effects on fibroblast cells mainly in high concentrations. Compounds 2 (IC50?=?99.9 mu M for L. amazonensis and IC50?=?90.5 mu M for L. braziliensis) and 3 (IC50?=?122.9 mu M for L. amazonensis and IC50?=?109.8 mu M for L. brasiliensis) were less active than dillapiole (1). Regarding the molecular properties, the conformational arrangement of the side chain, electronic features, and the hydrophilic/hydrophobic balance seem to be relevant for explaining the antileishmanial activity of dillapiole and its analogues.

Multiple trichoblastomas in a dog

Background – Hair follicle tumours generally present as benign, solitary masses and have a good prognosis following surgical resection. Hypothesis/Objectives – This report describes a case of multiple trichoblastomas in a dog. Animal – A 2-year-old crossbred dog presented with multiple soft cutaneous periocular, perilabial, submandibular and nasal nodules, between 2 and 9 cm in diameter, located on the right side of the face. New nodules were observed on the same side of the face at a second consultation 3 weeks later. Methods – Surgical resection of all nodules was performed in two procedures. Three nodules were initially resected and submitted for histolopathology and immunohistochemistry. The diagnosis was trichoblastoma for all three. At the time of the second consultation, new and remaining nodules were biopsied and the diagnosis of trichoblastoma confirmed. The dog was treated with doxorubicin and piroxicam for 30 days prior to the second surgical procedure in an attempt to reduce new tumour growth and the size of present tumours. All nodules were resected and the defects closed using rotation flaps. Results – No recurrence of the neoplasm was noted within 10 months after surgery. Conclusions and clinical importance – Trichoblastomas are generally benign but can present as multiple neoplasms that may require surgical resection and may respond to chemotherapy. To the authors’ knowledge, this is the first report of multiple trichoblastomas in a dog.