Lesões orais secundárias à leishmaniose visceral em um cão com hiperadrenocorticismo endógeno: relato de caso / Oral lesions secondary to visceral leishmaniasis in a dog with endogenous hyperadrenocorticism: case report

O objetivo do presente trabalho foi relatar um caso de leishmaniose visceral com apresentação mucosa em um cão com hiperadrenocorticismo. Um canino, macho, da raça Poodle, 11 anos de idade, foi atendido com histórico de disfagia, halitose e sialorreia. Ao exame físico, observou-se linfadenomegalia generalizada e alterações cutâneas, como rarefação pilosa, comedões, telangiectasia e atrofia cutânea. Além disso, o animal também apresentava formações orais localizadas na língua. Dos exames hematológicos e bioquímicos realizados, a única alteração encontrada foi elevação da fosfatase alcalina (1724u/L). O teste de supressão com a dexametasona em dose baixa foi executado para investigar hiperadrenocorticismo, tendo resultado positivo. Também foram realizados exames citológicos dos linfonodos, da medula óssea e das formações orais, tendo sido observada a presença de formas amastigotas de Leishmania sp. em todas as amostras. O animal foi submetido à biópsia incisional das formações orais, e a análise histopatológica demonstrou um quadro de inflamação granulomatosa com presença de grande quantidade de microrganismos morfologicamente compatíveis com formas amastigotas de Leishmania sp. no interior das células inflamatórias. Diante dos achados clínicos e dos exames complementares, diagnosticou-se um caso de leishmaniose com manifestação mucosa atípica, associado ao hiperadrenocorticismo, podendo essa endocrinopatia ter sido um fator predisponente para essa enfermidade infectocontagiosa.(AU)

The objective of the present study was to report a case of visceral leishmaniasis with mucosal presentation in a dog with hyperadrenocorticism. A canine, male, Poodle, 11 years old, was attended with a history of dysphagia, halitosis, and sialorreia. The physical examination revealed generalized lymphadenomegaly and cutaneous alterations such as hair loss, comedones, telangiectasia, and cutaneous atrophy. Futhermore, the animal also had localized oral formations on the tongue. From the hematological and biochemical tests performed, the only alteration was alkaline phosphatase elevation (1724u / L). The low dose dexamethasone suppression test was performed to investigate hyperadrenocorticism and found a positive result. In addition, cytological exams of lymph nodes, bone marrow and oral formations were also performed, and the presence of amastigote forms of Leishmania sp. were observed in all samples. The animal was submitted to incisional biopsy of the oral formations and the histopathological analysis showed a granulomatous inflammation with presence of large quantity of microorganisms morphologically compatible with amastigotes forms of Leishmania sp. within the inflammatory cells. Faced with clinical findings and complementary exams, a case of leishmaniasis with atypical mucosal manifestation, associated with hyperadrenocorticism, was diagnosed, and this endocrinopathy could have been a predisposing factor to this infectious-contagious disease.(AU)

Antioxidant effect of 4-nerolidylcatechol and -tocopherol in erythrocyte ghost membranes and phospholipid bilayers

4-Nerolidylcatechol (4-NC) is found in Pothomorphe umbellata root extracts and is reported to have a topical protective effect against UVB radiation-induced skin damage, toxicity in melanoma cell lines, and antimalarial activity. We report a comparative study of the antioxidant activity of 4-NC and α-tocopherol against lipid peroxidation initiated by two free radical-generating systems: 2,2′-azobis(2-aminopropane) hydrochloride (AAPH) and FeSO4/H2O2, in red blood cell ghost membranes and in egg phosphatidylcholine (PC) vesicles. Lipid peroxidation was monitored by membrane fluidity changes assessed by electron paramagnetic resonance spectroscopy of a spin-labeled lipid and by the formation of thiobarbituric acid-reactive substances. When lipoperoxidation was initiated by the hydroxyl radical in erythrocyte ghost membranes, both 4-NC and α-tocopherol acted in a very efficient manner. However, lower activities were observed when lipoperoxidation was initiated by the peroxyl radical; and, in this case, the protective effect of α-tocopherol was lower than that of 4-NC. In egg PC vesicles, malondialdehyde formation indicated that 4-NC was effective against lipoperoxidation initiated by both AAPH and FeSO4/H2O2, whereas α-tocopherol was less efficient in protecting against lipoperoxidation by AAPH, and behaved as a pro-oxidant for FeSO4/H2O2. The DPPH (2,2-diphenyl-1-picrylhydrazyl) free-radical assay indicated that two free radicals were scavenged per 4-NC molecule, and one free radical was scavenged per α-tocopherol molecule. These data provide new insights into the antioxidant capacity of 4-NC, which may have therapeutic applications for formulations designed to protect the skin from sunlight irradiation.