Cafarchia C, Dell'Aquila M E, Capelli G, Minoia P, Otranto D
Department of Animal Health and Welfare, Faculty of Veterinary Medicine, University of Bari, Bari, Italy.
Med Mycol. 2007 Feb;45(1):11-5. doi: 10.1080/13693780600962718.
Malassezia spp. are lipophilic yeasts that are part of the normal cutaneous microflora and sometimes act as pathogens causing dermatitis. This study investigated the interactions occurring between beta-endorphin and phospholipase activity in isolates of M. pachydermatis in dogs presenting cutaneous lesions. Phospholipase production was evaluated and quantified on 144 isolates suspended in Dixon broth to which different beta-endorphin concentrations (from 600 to 0.6 pM) were added. The isolates were divided into three groups: group A comprised isolates from lesional skin of dogs with dermatitis confined to one site, group B consisted of isolates from the healthy skin of the same dogs with localized lesions, and group C was made up of isolates from assorted skin sites of healthy dogs. A statistically higher phospholipase activity than that of the controls was recorded in group B at all tested beta-endorphin concentrations. In groups A (Pz=0.62) and C (Pz=0.62) phospholipase activity was statistically higher than the controls only at a concentration of 600 pM. This study suggests that beta-endorphin plays an important role in the production of phospholipase in M. pachydermatis isolates and provides evidence that beta-endorphin concentrations affect the number but not the Pz value of phospholipase-producing isolates. B-endorphin concentrations may play a relevant role in inducing M. pachydermatis cell differentiation towards the production or non-production of phospholipase.
马拉色菌属是亲脂性酵母，是正常皮肤微生物群的一部分，有时作为病原体引起皮炎。本研究调查了患有皮肤病变的犬只皮屑芽胞菌分离株中β-内啡肽与磷脂酶活性之间的相互作用。对悬浮于 Dixon 肉汤中的 144 株分离株进行磷脂酶产生情况评估和定量，向肉汤中添加不同浓度的β-内啡肽（从 600 到 0.6 pM）。分离株分为三组：A 组包括来自皮炎局限于一个部位的犬只病变皮肤的分离株，B 组由来自同一患有局部病变犬只健康皮肤的分离株组成，C 组由来自健康犬只不同皮肤部位的分离株组成。在所有测试的β-内啡肽浓度下，B 组记录到的磷脂酶活性在统计学上高于对照组。在 A 组（Pz = 0.62）和 C 组（Pz = 0.62）中，仅在 600 pM 浓度下磷脂酶活性在统计学上高于对照组。本研究表明，β-内啡肽在皮屑芽胞菌分离株中磷脂酶的产生中起重要作用，并提供证据表明β-内啡肽浓度影响产生磷脂酶的分离株数量，但不影响其 Pz 值。β-内啡肽浓度可能在诱导皮屑芽胞菌细胞向产生或不产生磷脂酶的方向分化中起相关作用。
