Animal Parasitology Department, Veterinary Institute, Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil.
Parasitol Res. 2013 Feb;112(2):501-9. doi: 10.1007/s00436-012-3159-4. Epub 2012 Nov 9.
The tick's fat body plays an essential role in energy storage and utilization. This study aimed to analyze the fat body neutral lipid composition in Rhipicephalus microplus engorged females. In the first study (physiological profile of untreated ticks), the lipid analysis took place over the course of 4 days; the engorged females were incubated at optimal conditions and their fat bodies were dissected daily. Fat body lipid analysis after fungal infection with Metarhizium anisopliae sensu lato (s.l.) or Beauveria bassiana s.l. was performed with four groups: one without any treatment, one that was inoculated with a solution of 0.1 % Tween 80 in water, and two groups that were inoculated with M. anisopliae or B. bassiana conidial suspensions. The fat bodies were dissected 24 and 48 h after infection. Lipid analysis was conducted by thin-layer chromatography on a silica plate. The results of the physiological profile showed that the amounts of triacylglycerol (TAG) and free cholesterol (CHO) decreased with time, whereas cholesterol ester (CHOE) increased on the second and fourth days. Following M. anisopliae or B. bassiana infection, there was an increase in the amount of CHO after 24 h, whereas the other lipid classes were not altered. M. anisopliae caused an increase in CHOE and TAG and a reduction in CHO at 48 h after infection; however, B. bassiana infection did not cause significant alterations in the concentrations of these lipids. M. anisopliae and B. bassiana infection changed the fat body metabolism of engorged female R. microplus ticks. This study provides the first report of changes in the neutral lipid composition of the R. microplus fat body.
蜱虫的肥大体在能量储存和利用中起着重要作用。本研究旨在分析饱血雌蜱 Rhipicephalus microplus 肥大体的中性脂类组成。在第一项研究（未经处理的蜱虫生理特征）中，脂质分析在 4 天内进行；将饱血雌蜱在最佳条件下孵育，并每天解剖它们的肥大体。在感染 Metarhizium anisopliae sensu lato（s.l.）或 Beauveria bassiana s.l. 真菌后，对脂肪体脂质进行了分析，共分为 4 组：一组不进行任何处理，一组用 0.1%吐温 80 水溶液接种，另外两组分别用 M. anisopliae 或 B. bassiana 分生孢子悬浮液接种。感染后 24 和 48 小时解剖脂肪体。通过薄层层析在硅胶板上进行脂质分析。生理特征的结果表明，三酰基甘油（TAG）和游离胆固醇（CHO）的含量随时间减少，而胆固醇酯（CHOE）在第二天和第四天增加。感染 M. anisopliae 或 B. bassiana 后，24 小时后 CHO 的含量增加，而其他脂质类没有变化。感染 M. anisopliae 后 48 小时，CHOE 和 TAG 增加，CHO 减少；然而，B. bassiana 感染并未导致这些脂质浓度发生显著变化。M. anisopliae 和 B. bassiana 感染改变了饱血雌蜱 R. microplus 的脂肪体代谢。本研究首次报道了 R. microplus 脂肪体中性脂类组成的变化。
